Updated on 2024/10/02

Information

 

写真a

 
HARADA YUICHI
 
Organization
Academic Research and Industrial Collaboration Management Office of Kyushu University Academic Research and Industrial Collaboration Management Office of Kyushu University(AiRIMaQ) Professor
Academic Research and Industrial Collaboration Management Office of Kyushu University (Concurrent)
Integrated Initiative for Designing Future Society (Concurrent)
Abolition organization Open Innovation Platform(Concurrent)
Kyushu University Platform of Inter/Transdisciplinary Energy Research (Concurrent)
Robert T.Huang Entreprenuership Center of Kyushu University(QREC) (Concurrent)
Abolition organization Global Innovation Center(Concurrent)
Interdisciplinary Graduate School of Engineering Sciences Department of Interdisciplinary Engineering Sciences(Concurrent)
Faculty of Information Science and Electrical Engineering Quantum Computing System Center(Concurrent)
Graduate School of Information Science and Electrical Engineering Education Center for Semiconductors and Value Creation(Concurrent)
Title
Professor
Contact information
メールアドレス
Tel
0925838881
Profile
Considering the collaborative relationship between university and industry made me set up the KOINE concept. KOINE is the abbreviation of Kyudai global Open Innovation Network Engine, but it is an English word that originated from ancient Greek. Koine represents a common language. KOINE concept provides the opportunities to meet and discuss freely people with different backgrounds and we expect such discussion can create multidisciplinary research as well as new and innovative industrial applications. KOINE concept promotes various research platforms and we study what is the essence of innovative creation and how innovative idea comes out.
Homepage

Research Areas

  • Humanities & Social Sciences / Educational technology

  • Natural Science / Magnetism, superconductivity and strongly correlated systems

Degree

  • Ph. D. ( 1991.3 Tokyo Institute of Technology )

Research History

  • Isuue Driven Team  

    Kyushu University Open Innovation Platform

    2024.4

  • 日本電話株式会社 1994-2015   

    日本電話株式会社

    1994.4 - 2015.3

  • Chalmers University of Technology, Gothenberg, Sweden 1992-1994 Oxford University, UK 2004-2007   

Research Interests・Research Keywords

  • Research theme: entrepreneurship

    Keyword: entrepreneurship

    Research period: 2024

  • Research theme: Open Innovation

    Keyword: Open Innovation

    Research period: 2024

  • Research theme: superconductivity

    Keyword: superconductivity

    Research period: 2024

  • Research theme: quantum circuit

    Keyword: quantum circuit

    Research period: 2024

  • Research theme: Nanofabrication of carbon family

    Keyword: carbon, nanotechnology

    Research period: 2022.4 - 2024.3

  • Research theme: Freezing and thawing mechanisms on CAS

    Keyword: CAS freezing thawing

    Research period: 2020.4 - 2021.3

  • Research theme: Industrial-academia research collaborations based on KOINE model or Kyudai global Open Innovation Network Engine that is an original open innovation system.

    Keyword: Open Innovation

    Research period: 2016.10 - 2021.9

  • Research theme: fabrication on superconducting qubits

    Keyword: superconductivity, qubit, nanotechnology, ALD

    Research period: 2015.4 - 2027.3

  • Research theme: Study on the management of the collaborative research projects among industry, academia, and government Innovative education

    Keyword: management of the collaborative research

    Research period: 2015.4 - 2017.3

Papers

  • Atomic layer deposition of aluminum (111) thin film by dimethylethylaminealane precursor Reviewed International journal

    #Sameh Okashaa, @Yoshiaki Sekine, @Satoshi Sasaki, Yuichi Haradaa

    Thin Solid Films   732   138784   2021.6

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    We report the growth of aluminum (111) thin film by atomic layer deposition (ALD) technique with dimethy- lethylaminealane (DMEAA) as a precursor. It is found that the metallic underlayer is essential to grow uniform aluminum films by DMEAA precursor. As a titanium thin film is used as the underlayer, grown aluminum thin film shows (111) orientation irrespective of substrates. The lattice constant and superconducting transition temperature of the aluminum thin films are the same as the bulk one. These findings suggest that ALD technique provides high quality of the aluminum thin films and have potential for the applications of superconducting devices. We discuss ALD technique with DMEAA precursor is the promising method for fabricating vertical small Josephson tunnel junctions, which can be used as the superconducting quantum bits.

    DOI: https://doi.org/10.1016/j.tsf.2021.138784

  • Andreev reflection and bound state formation in a ballistic two-dimensional electron gas probed by a quantum point contact Reviewed International journal

    Hiroshi Irie, Clements Todt, Norio Kumada, Harada, Yuichi, Hiroki Sugiyama, Tatsushi Akazaki, Koji Muraki

    Physical Review B   94   155305 - 6   2016.10

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    We study coherent transport and bound state formation of Bogoliubov quasiparticles in a high-mobility In0.75Ga0.25As two-dimensional electron gas (2DEG) coupled to a superconducting Nb electrode by means of a quantum point contact (QPC) as a tunable single-mode probe. Below the superconducting critical temperature of Nb, the QPC shows a single-channel conductance greater than the conductance quantum 2e2/h at zero bias, which indicates the presence of Andreev-reflected quasiparticles, time-reversed states of the injected electron, returning back through the QPC. The marked sensitivity of the conductance enhancement to voltage bias and perpendicular magnetic field suggests a mechanism analogous to reflectionless tunneling—a hallmark of phase-coherent transport, with the boundary of the 2DEG cavity playing the role of scatterers. When the QPC transmission is reduced to the tunneling regime, the differential conductance vs bias voltage probes the single-particle density of states in the proximity area. Measured conductance spectra show a double peak within the superconducting gap of Nb, demonstrating the formation of Andreev bound states in the 2DEG. Both of these results, obtained in the open and closed geometries, underpin the coherent nature of quasiparticles, i.e., phase-coherent Andreev reflection at the InGaAs/Nb interface and coherent propagation in the ballistic 2DEG.

    DOI: 10.1103/PhysRevB.94.155305

  • Josephson coupling through one-dimensional ballistic channel in semiconductor-superconductor hybrid quantum point contacts Reviewed International journal

    Harada, Yuichi, Iriel, Hiroshi, Sugiyama, Hiroki, Akazaki, Tatsushi

    PHYSICAL REVIEW B   89 ( 16 )   2014.4

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    We study a superconducting quantum point contact made of a narrow In0.75Ga0.25As channel with Nb proximity electrodes. The narrow channel is formed in a gate-fitted constriction of InGaAs/InAlAs/InP heterostructure hosting a two-dimensional electron gas.When the channel opening is varied with the gate, the Josephson critical current exhibits a discretized variation that arises from the quantization of the transverse momentum in the channel. The quantization of Josephson critical current persists down to the single-channel regime, providing an unambiguous demonstration of a semiconductor-superconductor hybrid Josephson junction involving only a single ballistic channel.

    DOI: 10.1103/PhysRevB.89.165415

  • Atomic layer deposition of self‐assembled aluminum nanoparticles using dimethylethylamine alane as precursor and trimethylaluminum as an initiator Reviewed

    Sameh Okasah and Yuichi Harada

    Journal of Nanoparticle Research   24   2022.11

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    DOI: https://doi.org/10.1007/s11051-022-05618-w

  • Ultra-fine metal gate operated graphene optical intensity modulator Reviewed

    Rai Kou, Yosuke Hori, Tai Tsuchizawa, Kaori Warabi, Yuzuki Kobayashi, Yuichi Harada, Hiroki Hibino, Tsuyoshi Yamamoto, Hirochika Nakajima, Koji Yamada

    Applied Physics Letters   109 ( 25 )   2016.12

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    A graphene based top-gate optical modulator on a standard silicon photonic platform is proposed for the future optical telecommunication networks. On the basis of the device simulation, we proposed that an electro-absorption light modulation can be realized by an ultra-narrow metal top-gate electrode (width less than 400 nm) directly located on the top of a silicon wire waveguide. The designed structure also provides excellent features such as carrier doping and waveguide-planarization free fabrication processes. In terms of the fabrication, we established transferring of a CVD-grown mono-layer graphene sheet onto a CMOS compatible silicon photonic sample followed by a 25-nm thick ALD-grown Al2O3 deposition and Source-Gate-Drain electrodes formation. In addition, a pair of low-loss spot-size converter for the input and output area is integrated for the efficient light source coupling. The maximum modulation depth of over 30% (1.2 dB) is observed at a device length of 50 μm, and a metal width of 300 nm. The influence of the initial Fermi energy obtained by experiment on the modulation performance is discussed with simulation results.

    DOI: 10.1063/1.4972306

  • Graphene optical modulator on silicon waveguide controlled by fine metal-Top gate

    D. Y. Hori, R. Kou, T. Tsuchizawa, Y. Kobayashi, Yuichi Harada, H. Hibino, T. Yamamoto, K. Yamada, H. Nakajima

    13th IEEE International Conference on Group IV Photonics, GFP 2016 2016 IEEE 13th International Conference on Group IV Photonics, GFP 2016   90 - 91   2016.11

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    We proposed a fine-metal gated graphene optical modulator on a CMOS compatible silicon photonic platform. A maximum extinction ratio of 1.2dB is realized by using a 25-nm thick Al
    2
    O
    3
    gate capacitor. Optimized device structure and initial Fermi energy dependences are discussed.

    DOI: 10.1109/GROUP4.2016.7739064

  • Nanowire-nanoantenna coupled system fabricated by nanomanipulation Invited Reviewed International journal

    Harada, Yuichi

    OPTICS EXPRESS   24 ( 8 )   8647 - 8659   2016.4

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    DOI: 10.1364/OE.24.008647

  • Detection of Coherent Terahertz Radiation from a High-Temperature Superconductor Josephson Junction by a Semiconductor Quantum-Dot Detector Invited Reviewed International journal

    Harada, Yuichi

    PHYSICAL REVIEW APPLIED   5 ( 2 )   2016.2

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    DOI: 10.1103/PhysRevApplied.5.024010

  • Gate-controlled semimetal-topological insulator transition in an InAs/GaSb heterostructure Invited Reviewed International journal

    Harada, Yuichi

    PHYSICAL REVIEW B   91 ( 24 )   2015.6

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    DOI: 10.1103/PhysRevB.91.245309

  • Self-aligned gate-all-around InAs/InP core-shell nanowire field-effect transistors Reviewed International journal

    Harada, Yuichi

    JAPANESE JOURNAL OF APPLIED PHYSICS   54 ( 4 )   2015.4

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    DOI: 10.7567/JJAP.54.04DN04

  • Emission enhancement in nanowire-nanoantenna system fabricated by nanomanipulation

    M. Ono, E. Kuramochi, G. Zhang, H. Sumikura, Y. Harada, D. Cox, M. Notomi

    27th IEEE Photonics Conference, IPC 2014 2014 IEEE Photonics Conference, IPC 2014   532 - 533   2014.12

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    We fabricated a unique system in which a semiconductor nanowire and a gold bowtie nanoantenna are combined. InP nanowire is precisely placed in the nanogap of the nanoantenna with a nanomanipulator installed in a focused ion beam system. By measuring the intensity mapping of the photoluminescence from the nanowire, we observed a significantly large enhancement at the antenna gap. We also calculated the electric field numerically, and the simulated results showed that the large enhancement that is obtained was caused by plasmonic resonance and was affected by the breakdown of the field suppression effect in the subwavelength nanowire.

    DOI: 10.1109/IPCon.2014.6995485

  • Observation of neuronal death in vitro by SEM and optical microscopy Reviewed

    Nahoko Kasai, Rick Lu, Touichiro Goto, Aya Tanaka, Shingo Tsukada, Yuichi Harada, Koji Sumitomo

    e-Journal of Surface Science and Nanotechnology   12   179 - 184   2014.4

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    We observed neurons cultivated on an indium tin oxide (ITO) substrate using scanning electron microscopy (SEM) whose high spatial resolution allows us to observe neuronal morphological details. First, we optimized the fixation condition of cultivated neurons for SEM observation. The first fixation with paraformaldehyde and glutaraldehyde, and the second fixation with OsO4 were both necessary to avoid cell removal during the preparation before SEM observation. After optimization, we examined the morphological changes of neurons under an apoptotic condition, induced by staurosporine, by using both SEM and an immunochemical technique. Interestingly, the addition of staurosporine induced both apoptosis and a necrotic phenomenon. Immunostaining analysis revealed late-stage apoptosis after early-stage apoptosis, which was observed induced in cortical neurons by staurosporine for the first time. We confirmed that the SEM imaging of neurons is very useful as regards observing the apoptotic process. It is also a promising tool for understanding such neuronal activities as synaptic formation and axonal growth. Further examination of the interaction between neurons and substrates will contribute to the implementation of the artificial neurological devices.

    DOI: 10.1380/ejssnt.2014.179

  • Fabrication of a ring structure at the aperture of a hole for the efficient suspension of a lipid bilayer Reviewed

    Toichiro Goto, Yuichi Harada, David Cox, Koji Sumitomo

    Japanese Journal of Applied Physics   53 ( 9 )   2014.1

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    We propose a hydrophilic-raised-ring structure at the aperture of a hole for the efficient suspension of a lipid bilayer. This ring structure can be fabricated by using a combination consisting of a focused ion beam (FIB) and a hydrogen silsesquioxane (HSQ) negative electron beam (EB) resist layer on a substrate. Negative EB resist at the aperture of a hole can be selectively reacted with a scattered gallium ion beam during the FIB milling process, and a ring structure can be obtained by employing a development process. Assessments of the cross section of the ring revealed a two-step structure. The suspension of lipid bilayers on the ring structures was assessed by observing the green fluorescence of calcein dye inside the holes. Our observation of fluorescent images showed that the lipid bilayers on the ring structures sealed the calcein solutions. This result indicates that our fabrication processes can be used to produce nanobio devices that need lipid bilayer suspensions.

    DOI: 10.7567/JJAP.53.096503

  • Effects of hydrogen intercalation on transport properties of quasi-free-standing monolayer graphene Reviewed

    Shinichi Tanabe, Makoto Takamura, Yuichi Harada, Hiroyuki Kageshima, Hiroki Hibino

    Japanese Journal of Applied Physics   53 ( 4 SPEC. ISSUE )   2014.1

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    We report that mobility in quasi-free-standing monolayer graphene grown on SiC(0001), when compared at the same carrier density, depends on the annealing temperature used for hydrogen intercalation. This was verified by measuring mobility in top-gated devices using quasi-freestanding monolayer graphene obtained by annealing at different temperatures. The density of charged impurities varies with annealing temperature, and it influences transport properties. Our systematic investigation shows that annealing temperatures between 700 and 800 °C are optimum for obtaining high-mobility quasi-free-standing monolayer graphene with the lowest number of charged impurities.

    DOI: 10.7567/JJAP.53.04EN01

  • Unipolar behavior in graphene-channel field-effect-transistors with n-type doped SiC source/drain regions Reviewed

    Yuichi Nagahisa, Yuichi Harada, Eisuke Tokumitsu

    Applied Physics Letters   103 ( 22 )   2013.11

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    To realize graphene-channel field-effect-transistors (GFETs) with unipolar behavior and high on/off current ratios, we fabricated and characterized top-gate GFETs with n-type doped SiC (n-SiC) source/drain (S/D) regions on 4H-SiC(0001) substrates. 0-2 mono-layers (MLs) of graphene were grown on a monoatomic interfacial layer called zero-layer (ZL) by vacuum annealing. The 0-2 graphene MLs on the ZL were converted into 1-3 MLs of graphene without a ZL by annealing in H2. The GFETs with n-SiC S/D regions and 1-3 MLs of graphene without a ZL showed unipolar behavior with a high on/off current ratio of 2.7 × 103.

    DOI: 10.1063/1.4833755

  • Encapsulated gate-all-around InAs nanowire field-effect transistors Reviewed

    Satoshi Sasaki, Kouta Tateno, Guoqiang Zhang, Henri Suominen, Yuichi Harada, Shiro Saito, Akira Fujiwara, Tetsuomi Sogawa, Koji Muraki

    Applied Physics Letters   103 ( 21 )   2013.11

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    We report the fabrication of lateral gate-all-around InAs nanowire field-effect transistors whose gate overlaps the source and drain electrodes and thus fully encapsulates the nanowire channel. They feature large drive current and transconductance that surpass those of conventional non-gate-overlap devices. The improved device characteristics can be attributed to the elimination of access resistance associated with ungated segments between the gate and source/drain electrodes. Our data also reveal a correlation between the normalized transconductance and the threshold voltage, which points to a beneficial effect of our wet-etching procedure performed prior to the atomic-layer-deposition of the gate dielectric.

    DOI: 10.1063/1.4832058

  • High-temperature characteristics in recessed-gate AlGaN/GaN enhancement-mode heterostructure field effect transistors with enhanced-barrier structures Reviewed

    Narihiko Maeda, Masanobu Hiroki, Satoshi Sasaki, Yuichi Harada

    Japanese journal of applied physics   52 ( 8 PART 2 )   2013.8

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    Recessed-gate AlGaN/GaN enhancement-mode (E-mode) heterostructure field-effect transistors (HFETs) with enhanced-barrier structures were fabricated, and their high-temperature characteristics were examined. Owing to enhanced-barrier structures, where a thin AlGaN layer with a higher Al composition is inserted into the AlGaN barrier, excellent E-mode operation with threshold voltage (Vth) higher than +3 V and drain current density (Id) higher than 600mA/mm was obtained at room temperature. Interestingly, Id did not decrease much at high temperatures, i.e., Id decreased from 610 to 590mA upon a temperature raise from RT to 300 °C. Open-gate devices with and without recessed-gate structures were fabricated and their two-terminal characteristics were comparatively examined, revealing that the observed peculiar characteristics are ascribed to recessed-gate structures. A model for explaining the observed high-temperature characteristics is proposed.

    DOI: 10.7567/JJAP.52.08JN18

  • Edge channel transport in the InAs/GaSb topological insulating phase Reviewed

    Kyoichi Suzuki, Yuichi Harada, Koji Onomitsu, Koji Muraki

    Physical Review B - Condensed Matter and Materials Physics   87 ( 23 )   2013.6

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    Transport in InAs/GaSb heterostructures with different InAs layer thicknesses is studied using a six-terminal Hall bar geometry with a 2-μm edge channel length. For a sample with a 12-nm-thick InAs layer, nonlocal resistance measurements with various current/voltage contact configurations reveal that the transport is dominated by edge channels with a negligible bulk contribution. Systematic nonlocal measurements allow us to extract the resistance of individual edge channels, revealing sharp resistance fluctuations indicative of inelastic scattering. Our results show that the InAs/GaSb system can be tailored to have conducting edge channels while keeping a gap in the bulk region and provide a way of studying two-dimensional topological insulators even when quantized transport is absent.

    DOI: 10.1103/PhysRevB.87.235311

  • Slow noise processes in superconducting resonators Reviewed

    J. Burnett, T. Lindström, M. Oxborrow, Y. Harada, Y. Sekine, P. Meeson, A. Ya Tzalenchuk

    Physical Review B - Condensed Matter and Materials Physics   87 ( 14 )   2013.4

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    Slow noise processes, with characteristic timescales ∼1 s, have been studied in planar superconducting resonators. A frequency-locked loop is employed to track deviations of the resonator center frequency with high precision and bandwidth. Comparative measurements are made in varying microwave drive and temperature, and between bare resonators and those with an additional dielectric layer. All resonators are found to exhibit flicker frequency noise which increases with decreasing microwave drive. We also show that an increase in temperature results in a saturation of flicker noise in resonators with an additional dielectric layer, while bare resonators stop exhibiting flicker noise, instead showing a random frequency walk process.

    DOI: 10.1103/PhysRevB.87.140501

  • Quantum hall effect and carrier scattering in quasi-free-standing monolayer graphene Reviewed

    Shinichi Tanabe, Makoto Takamura, Yuichi Harada, Hiroyuki Kageshima, Hiroki Hibino

    Applied Physics Express   5 ( 12 )   2012.12

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    The quantum Hall effect has been observed in quasi-free-standing monolayer graphene on SiC for the first time. This was achieved by decreasing the carrier density while applying gate voltage in top-gated devices. The charge neutrality point was also clearly observed, which has not been reported in top-gated structures. The mobilities at constant carrier densities did not show apparent temperature dependence up to 300 K, and conductivity was linearly dependent on carrier density. These results indicate that Coulomb scattering induced by charged impurities limits the mobility of quasi-free-standing monolayer graphene up to 300 K.

    DOI: 10.1143/APEX.5.125101

  • Diamond field-effect transistors with 1.3A/mm drain current density by Al 2O 3 passivation layer Reviewed

    Kazuyuki Hirama, Hisashi Sato, Yuichi Harada, Hideki Yamamoto, Makoto Kasu

    Japanese journal of applied physics   51 ( 9 )   2012.9

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    Using nitrogen-dioxide (NO 2) adsorption treatment and Al 2O 3 passivation technique, we improved drain current (IDS) of hydrogen-terminated (Hterminated) diamond field-effect transistors (FETs). The Al 2O 3 passivation layer also serves as a gate-insulator in a gate region. Maximum IDS (I DSmax) of -1:35A/mm was obtained for the diamond FETs with NO 2 adsorption and the Al 2O 3 passivation layer. This I DSmax is the highest ever reported for diamond FETs and indicates that the Al 2O 3 passivation layer can stabilize adsorbed NO 2, which increases the hole carrier concentration on the H-terminated diamond surface. In RF small-signal characteristics, the diamond FETs with NO 2 adsorption and the Al 2O 3 passivation layer showed high cutoff-frequency (fT) and maximum frequency of oscillation (f max) in a wide gate-source voltage (VGS) range (>10 V). This is because the Al 2O 3 gate insulator with a high potential barrier against hole carriers can confine and control the high concentration of hole carriers and then high forward-bias voltage can be applied without noticeable gate leakage current.

    DOI: 10.1143/JJAP.51.090112

  • High-temperature characteristics in normally off AlGaN/GaN heterostructure field-effect transistors with recessed-gate enhanced-barrier structures Reviewed

    Narihiko Maeda, Masanobu Hiroki, Satoshi Sasaki, Yuichi Harada

    Applied Physics Express   5 ( 8 )   2012.8

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    High-temperature characteristics in normally off AlGaN/GaN heterostructure field-effect transistors (HFETs) with recessed-gate enhanced-barrier structures were examined up to 300 °C, where a high threshold voltage (V th) of +3.0 V and a high drain current density (I d) of 610mA/mm were obtained at room temperature (RT). Interestingly, Id did not degrade significantly up to 300 °C with a small positive shift in Vth from +3.0 to +3.5 V. A model has been proposed that channel electrons should experience a potential step when they pass the nonrecessed/recessed boundary region in recessed-gate structures, which should be related to the observed high-temperature characteristics.

    DOI: 10.1143/APEX.5.084201

  • Thermally stable operation of h-terminated diamond FETs by NO 2 adsorption and Al 2O 3 passivation Reviewed

    Kazuyuki Hirama, Hisashi Sato, Yuichi Harada, Hideki Yamamoto, Makoto Kasu

    IEEE Electron Device Letters   33 ( 8 )   1111 - 1113   2012.7

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    Using the NO 2 adsorption and Al 2O 3 passivation technique, we improved the thermal stability of hydrogen-terminated diamond field-effect transistors (FETs) and then demonstrated stable operation at 200 °C in a vacuum for the first time. At 200 °C, the drain current I DS of a passivated diamond FET remained constant for at least more than 2 h. No degradation of FET characteristics was observed after the 200 °C heating cycle. Furthermore, a passivated diamond FET with a gate length of 0.2 μm showed high maximum I DS of-1000 mA/mm and an RF output power density of 2 W/mm.

    DOI: 10.1109/LED.2012.2200230

  • In 0:75Ga0:25as quantum point contacts utilizing wrap-gate geometry Reviewed

    Hiroshi Irie, Yuichi Harada, Hiroki Sugiyama, Tatsushi Akazaki

    Applied Physics Express   5 ( 2 )   2012.2

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    A fabrication technique for quantum point contacts (QPCs) in an InGaAs/InAlAs two-dimensional electron gas heterostructure is reported. The key challenge in realizing a well-behaved QPC is efficient electrostatic control of a one-dimensional channel using the gate electrode. The fabricated QPCs employ a 100-nm-wide mesa constriction and a gate electrode that wraps around the constriction for three-dimensional electricfield gating. In addition, conformal aluminum-oxide growth by atomic layer deposition is employed to suppress gate leakage while minimizing the interface state density. The wrap-gate QPCs show clear conductance steps, demonstrating well-defined quantized transverse modes in the InGaAs-based one-dimensional channel.

    DOI: 10.1143/APEX.5.024001

  • Gate operation of InAs/AlGaSb heterostructures with an atomic-layer- deposited insulating layer Reviewed

    Kyoichi Suzuki, Yuichi Harada, Fumihiko Maeda, Koji Onomitsu, Toru Yamaguchi, Koji Muraki

    Applied Physics Express   4 ( 12 )   2011.12

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    Surface treatment of the GaSb cap layer is investigated for the gate operation of InAs/AlGaSb heterostructures with an Al 2O 3 insulating layer grown by atomic layer deposition. We show that dilute HCl treatment for only 10 s effectively removes the electron trap states at the GaSb/Al 2O 3 interface and greatly improves the gate operation. In contrast, HCl treatment followed by water rinse results in adverse effects. Using an equivalent circuit model, we deduce the interface trap state density for the no-treatment case to be D it ∼ 10 13cm -2eV -1, which is reduced to well below 10 12 cm -2eV -1 by the HCl treatment. Our data also show that deep donor states in the AlGaSb barrier impede the gate operation and cause gate hysteresis.

    DOI: 10.1143/APEX.4.125702

  • Aluminum oxide for an effective gate in Si/SiGe two-dimensional electron gas systems Reviewed

    Yun Sok Shin, Roland Brunner, Akihiro Shibatomi, Toshiaki Obata, Tomohiro Otsuka, Jun Yoneda, Yasuhiro Shiraki, Kentarou Sawano, Yasuhiro Tokura, Yuichi Harada, Koji Ishibashi, Seigo Tarucha

    Semiconductor Science and Technology   26 ( 5 )   2011.4

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    We investigate the gating properties of Si/SiGe two-dimensional electron gas systems with various gate materials and fabricate a lateral Si/SiGe quantum dot by gating through an Al2O3 film. In comparison to the conventional surface Schottky gates, gating through a thin Al2O 3 layer provides a strong suppression of leakage current. The fabricated quantum dot shows a periodic current oscillation or Coulomb oscillation with negligible gate leakage, indicating that the gating employed may be good for implementing Si/SiGe-based spin qubit devices with quantum dots.

    DOI: 10.1088/0268-1242/26/5/055004

  • A field-induced semiconductor quantum dot defined by a single metallic front-gate Reviewed

    A. Richter, K. Matsuda, Y. Harada, H. Tamura, T. Akazaki, Y. Hirayama, H. Takayanagi

    2nd International Conference on Semiconductor Quantum Dots, QD 2002 Physica Status Solidi C: Conferences   ( 4 )   1317 - 1320   2003.12

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    We present studies on the electronic transport in a quantum dot based on a back-gated undoped GaAs/AlGaAs heterostructure. A high-quality two-dimensional electron gas can be induced in the structure by applying a back-gate voltage. The quantum dot is well defined by means of a single metallic frontgate. We observe clear regions of Coulomb blockade and pronounced tunneling peaks in a broad range of source-drain and front-gate voltages. The formation of the quantum dot and energetic evolution of the associated tunneling peaks are studied as a function of the applied front-gate voltage. Excellent agreement to the calculated Coulomb diamond pattern using the 'constant interaction model' is achieved, if a front-gate voltage dependent change of the dot capacitance is taken into account.

    DOI: 10.1002/pssc.200303080

  • Anomalous magnetic flux periodicity of supercurrent in mesoscopic SNS Josephson junctions Reviewed

    Yuichi Harada, S. Jensen, T. Akazaki, H. Takayanagi

    Physica C: Superconductivity and its Applications   367 ( 1-4 )   229 - 233   2002.2

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    The anomalous flux periodicity of supercurrent in mesoscopic SNS Josephson junctions was measured. The flux focusing factor was examined in order to obtain the precise magnetic flux in the normal region. Results showed that the magnetic flux periodicity became twice, when the junction lengths was shorter than 400 nm.

    DOI: 10.1016/S0921-4534(01)01023-1

  • Superconducting junctions using AlGaAs/GaAs heterostructures with high Hc2 NbN electrodes Reviewed

    Hideaki Takayanagi, Tatsushi Akazaki, Minoru Kawamura, Yuichi Harada, Junsaku Nitta

    14th International Conference on the Physica E: Low-Dimensional Systems and Nanostructures   12 ( 1-4 )   922 - 926   2002.1

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    We investigated a superconductor-semiconductor-superconductor junction formed by two superconducting NbN electrodes and a two-dimensional electron gas (2DEG) in an AlGaAs/GaAs heterostructure. We obtained a good ohmic contact between NbN/AuGeNi electrodes and 2DEG by annealing them at 450 °C for 1 min in an N2 atmosphere. We observed a decrease in the resistance caused by Andreev reflection (AR) within the superconducting energy gap voltage in a zero magnetic field in this structure. We found that the peculiar features of the magnetoresistance in the transition region can be qualitatively explained by considering the existence of the AR in high magnetic fields.

    DOI: 10.1016/S1386-9477(01)00410-6

  • Highly sensitive and wideband optical detector in patterned YBa2Cu3O7-d thin film

    Ken'ichi Tanaka, Yuichi Harada, Martin Danerud, Matsuo Sekine, Motoichi Ohtsu

    Photodetectors: Materials and Devices II Proceedings of SPIE - The International Society for Optical Engineering   316 - 325   1997.12

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    We have demonstrated an optical detector based on patterned YBa2Cu3O7-δ thin films. The responses up to 18 GHz were observed using two wavelength lasers. The amplitude of the light was modulated up to 18 GHz by an optical heterodyne mixing system. The responsivity of the detectors is over 50 V/W for different wavelength lasers below 1 Hz and the responsivity is 4 mV/W at the 780 nm wavelength and 30 mV/W at 1.5 μm in the region from 3 GHz to 18 GHz. Our detector is one of the promising candidates for highly sensitive and wideband optical receiver.

  • Highly sensitive and wideband optical detection in patterned YBa2Cu3O7-δ thin films Reviewed

    Ken'ichi Tanaka, Yoshiro Arikawa, Matsuo Sekine, Motoichi Ohtsu, Yuichi Harada, Martin Danerud

    Applied Physics Letters   68 ( 22 )   3174 - 3176   1996.12

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    We have measured the optical responses up to 18 GHz in patterned YBa2Cu3O7-δ thin films at various wavelengths by optical heterodyne mixing. The responsivity of the detectors is higher than 50 V/W below 1 Hz at various wavelengths and the responsivity is 20 mV/W at 780 nm and 150 mV/W at 1.55 μm wavelengths in the regime of the modulation frequency from 3 GHz to 18 GHz.

    DOI: 10.1063/1.115815

  • Flux flow and vortex tunneling in two-dimensional arrays of small Josephson junctions Reviewed

    C. Chen, P. Delsing, D. Haviland, Y. Harada, T. Claeson

    Physical Review B - Condensed Matter and Materials Physics   54 ( 13 )   9449 - 9457   1996.1

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    We have measured the temperature dependence and magnetic field dependence of the zero-bias resistance ((Formula presented)) as well as the current-voltage (I-V) characteristics for several two-dimensional arrays of small aluminum Josephson junctions. (Formula presented)(T) decreases with decreasing temperature, which can be described in terms of two types of vortex motion: flux, flow, and vortex tunneling. At temperatures higher than the Kosterlitz-Thouless transition temperature (T>(Formula presented)) or at a bias current greater than the current corresponding to the onset of the nonlinear I-V characteristics (I>(Formula presented)), the effective damping resistance which characterizes flux-flow motion is found to be approximately equal to the junction normal-state resistance (Formula presented). At low temperatures and at small bias current, (Formula presented) is temperature independent and remains finite down to our minimum attainable temperature. This finite resistance is found to be dependent on the array size as well as the junction parameters.

    DOI: 10.1103/PhysRevB.54.9449

  • Cooper-pair tunneling in small junctions with tunable Josephson coupling Reviewed

    Yuichi Harada, Hideaki Takayanagi, Arkadi A. Odintsov

    Physical Review B - Condensed Matter and Materials Physics   54 ( 9 )   6608 - 6613   1996.1

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    We investigate Cooper-pair tunneling in a circuit consisting of two dc-superconducting quantum interference devices in series, with a gate capacitively coupled to the central island. Measurements cover a wide range of values of the ratio between Josephson coupling energy (Formula presented) and charging energy (Formula presented). The (Formula presented) ratio dependence of the supercurrent is well described by the orthodox theory provided that strong fluctuations of the Josephson phase due to the electromagnetic environment are taken into account. Our data can be interpreted in terms of squeezing of the charge fluctuations with decreasing (Formula presented) ratio.

    DOI: 10.1103/PhysRevB.54.6608

  • Coherent cooper-pair tunneling in a superconducting single electron transistor Reviewed

    Yuichi Harada, Hideaki Takayanagi, Arkadi A. Odintsov

    Japanese Journal of Applied Physics   34 ( 8 )   4572 - 4574   1995.8

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    We investigate how coherent Cooper-pair tunneling depends on the competition between Josephson coupling energy Ej and charging energy Eq. Measurements were performed on a circuit consisting of two dc-SQUIDs in series, with a gate capacitively coupled to the central island. As the Ej/Ec ratio decreased, coherent Cooper pairs tended to tunnel incoherently. Measured data show good agreement with theoretical calculations in strong and weak coupling limits. This experiment implies the manifestation of Heisenberg's uncertainty principle in a superconductor.

    DOI: 10.1143/JJAP.34.4572

  • Scaling behavior of the magnetic-field-tuned superconductor-insulator transition in two-dimensional Josephson-junction arrays Reviewed

    C. D. Chen, P. Delsing, D. B. Haviland, Yuichi Harada, T. Claeson

    Physical Review B   51 ( 21 )   15645 - 15648   1995.1

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    We have studied the superconductor-insulator (SI) phase transition for two-dimensional (2D) arrays of small Josephson junctions in a weak magnetic field. The data were analyzed within the context of the theory of the magnetic-field-tuned SI transition in 2D superconductors. We show resistance scaling curves over several orders of magnitude for the 2D arrays. The critical exponent zB is determined to be 1.05, in good agreement with the theory. Moreover, the transverse (Hall) resistance at the critical field is found to be very small in comparison to the longitudinal resistance.

    DOI: 10.1103/PhysRevB.51.15645

  • Fabrication and measurement of a Nb based superconducting single electron transistor Reviewed

    Y. Harada, D. B. Haviland, P. Delsing, C. D. Chen, T. Claeson

    Applied Physics Letters   65 ( 5 )   636 - 638   1994.12

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    A new four-layer resist system was developed to fabricate small capacitance niobium tunnel junctions. Nb/AlOx/Al junctions were used to make a superconducting single electron transistor composed of two dc SQUIDs in series. The current-voltage characteristics were measured and two types of resonant tunneling of Cooper pairs were observed at different magnetic fields.

    DOI: 10.1063/1.112255

  • Vortex mobility in two-dimensional arrays of small Josephson junctions Reviewed

    C. D. Chen, P. Delsing, D. B. Haviland, Y. Harada, T. Claeson

    Physica B: Physics of Condensed Matter   194-196 ( PART 1 )   989 - 990   1994.2

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    We have measured the temperature and magnetic field dependencies of the zero bias resistance for several 2D arrays of small aluminum Josephson junctions. The normal state resistances RN of the junctions vary between 2.2 and 7.5 kω whereas the ratio of Josephson coupling energy EJ to the charging energy Ec ranges between 4.3 and 0.6, where Ec= e2 2C, C being the junction capacitance. The vortex mobility is deduced from the frustration (i.e. the number of flux quantum per unit cell) dependence of zero bias resistance. The mobility decreases when the temperature is lowered, resulting in a decrease of resistance. Fitting the data to a simple exponential form, we find the barrier for the vortex hopping to be -aEJ, with a≈0.3. For all arrays, there exists a crossover temperature Tcr which separates the regime of thermally assisted hopping from that of quantum creep of vortices. For our samples, Tcr is close to the theoretically predicted value of ωp 2π, where ωp=(8EJEc) 1 2.

    DOI: 10.1016/0921-4526(94)90824-9

  • Magnetic flux and gate voltage modulation of the current in a superconducting loop of ultra-small tunnel junctions Reviewed

    Y. Harada, D. B. Haviland, C. D. Chen, P. Delsing, T. Claeson

    Physica B: Physics of Condensed Matter   194-196 ( PART 1 )   1015 - 1016   1994.2

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    We have measured the current-voltage (I-V) characteristics of a loop of four superconducting tunnel junctions at low temperatures (T≈50mK). In each branch of the loop, tunneling occurs through a small capacitance island (C≈1fF). In this geometry we can vary the magnetic flux Φ in the loop and the voltage Vg on gate electrodes, which have capacitance Cg to the small islands. We find that both Φ and Vg modulate the I-V curve.

    DOI: 10.1016/0921-4526(94)90837-0

  • Thermal activation and injection of charge solitons in 2D-arrays of small Josephson junctions. Reviewed

    P. Delsing, C. D. Chen, D. B. Haviland, Y. Harada, T. Claeson

    Physica B: Physics of Condensed Matter   194-196 ( PART 1 )   993 - 994   1994.2

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    We have measured the zero bias resistance, R0, and the threshold voltage, Vt, of 2D arrays of small Josephson junctions as functions of temperature and magnetic field. At low temperature, the Coulomb blockade dominates due to the relatively large charging energy EC= e2 2C (C being the junction capacitance). We find that the zero bias resistance may be described by thermal activation of charge solitons in most cases, i.e., R0≈k exp( Ea kBT). In the normal state, the activation energy Ea is close to 0.25 EC. The measured activation energy at low magnetic field is less than 0.25EC+Δ (where Δ is the superconducting gap), but larger than EC for all arrays. In a few samples, where the Josephson coupling energy EJ is relatively large, Ea oscillates with the magnetic field. The period of the oscillation corresponds to one flux quantum per unit cell and the amplitude is roughly EJ. In these samples the threshold voltage also oscillates at low magnetic fields. Such behavior of both Ea and Vt is a clear indication that also Cooper pair solitons contribute to the charge transport.

    DOI: 10.1016/0921-4526(94)90826-5

  • Vortex mobility in two-dimensional arrays of small Josephson junctions Reviewed

    C. D. Chen, P. Delsing, D. B. Haviland, Yuichi Harada, T. Claeson

    Proceedings of the 20th International Conference on Low Temperature Physics Physica B: Condensed Matter   194-96 ( pt 1 )   989 - 990   1994.1

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    We have measured the temperature and magnetic field dependencies of the zero bias resistance for several 2D arrays of small aluminum Josephson junctions. The normal state resistances RN of the junctions vary between 2.2 and 7.5 kΩ whereas the ratio of Josephson coupling energy EJ to the charging energy Ec ranges between 4.3 and 0.6, where Ec=e2/2C, C being the junction capacitance. The vortex mobility is deduced from the frustration (i.e. the number of flux quantum per unit cell) dependence of zero bias resistance. The mobility decreases when the temperature is lowered, resulting in a decrease of resistance. Fitting the data to a simple exponential form, we find the barrier for the vortex hopping to be -aEJ, with a≈0.3. For all arrays, there exists a crossover temperature Tcr which separates the regime of thermally assisted hopping from that of quantum creep of vortices. For our samples, Tcr is close to the theoretically predicted value of ℏω-p$//2π, where ℏω-p$/=(8EJEc) 1/2 .

    DOI: 10.1016/0921-4526(94)90824-9

  • Charge solitons and quantum fluctuations in two-dimensional arrays of small Josephson junctions Reviewed

    P. Delsing, C. D. Chen, D. B. Haviland, Yuichi Harada, T. Claeson

    Physical Review B   50 ( 6 )   3959 - 3971   1994.1

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    We have measured the current-voltage (IV) characteristics of several two-dimensional arrays of small Josephson junctions as a function of temperature, T and magnetic field B. The junctions have relatively large charging energies EC1 K, and normal-state resistances RN in the range of 4-150 kΩ. From the IV characteristics we can deduce the zero-bias resistance R0 and the threshold voltage Vt which reveal important information about the dynamics and statics of charge solitons in the array. R0(T) increases with decreasing temperature and may be described by thermal activation of charge solitons, characterized by an activation energy Ea. When the electrodes are in the normal state, Ea is close to 1/4EC. At low T, the thermal activation behavior breaks down, and R0(T) levels off to a value that can be attributed to the quantum fluctuations in the array. This interpretation places limitations on the observability of the charge unbinding, Kosterlitz-Thouless-Berezinskii transition for single electrons. When the electrodes are superconducting, Ea is much larger and dependent on B. In several samples, both Ea and Vt oscillate with B, having a period corresponding to one flux quantum per unit cell. For increasing magnetic fields, Vt increases until B250-450 G where it starts to decrease rapidly. We interpret the B dependence of Ea and Vt as a result of competition between Cooper-pair solitons and single-electron solitons.

    DOI: 10.1103/PhysRevB.50.3959

  • Observation of the resonant tunneling of cooper pairs Reviewed

    D. B. Haviland, Y. Harada, P. Delsing, C. D. Chen, T. Claeson

    Physical Review Letters   73 ( 11 )   1541 - 1544   1994.1

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    We demonstrate how the Coulomb blockade of tunneling and the coherent Josephson tunneling of electron pairs can coexist in the same experiment. Measurements were made on a circuit consisting of two dc SQUIDs connected in series, with a gate capacitively coupled to the center electrode. Peaks in the current as a function of bias voltage shifted position with gate voltage in agreement with the theory of resonant Cooper pair tunneling.

    DOI: 10.1103/PhysRevLett.73.1541

  • All-Nb thin film microbridge-type Josephson junction for submillimeter-wave detection Reviewed

    Nobumitsu Hirose, Yuichi Harada, Matsuo Sekine, Shigeru Yoshimori, Mitsuo Kawamura

    Infrared Physics   34 ( 5 )   445 - 455   1993.10

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    A copolymer of methyl methacrylate (MMA) and 3-triethoxysilylpropyl methacrylate (ESPMA) was proposed as a positive-working electron beam (EB) resist of a new type. It was found that it had 4-10 times the resistance of polymethylmethacrylate (PMMA) against CBrF3 plasma damage. The mechanism of etching Nb in reactive-ion-etching (RIE) was deciphered. Using the new EB resist and nanometer process technology, an all-Nb thin film microbridge was fabricated. It shows the a.c. Josephson effect, i.e. the Shapiro steps upto the 11th were observed under millimeter-wave (70 GHz) radiation. In addition the coherently working performance of the series array of these thin-film microbridges were observed definitively.

    DOI: 10.1016/0020-0891(93)90078-L

  • Ac Josephson effect in superconducting all-Nb thin-film nanobridges up to 693 GHz Reviewed

    Yoshinori Uzawa, Etsuo Kawate, Nobumitsu Hirose, Isao Motohashi, Yuichi Harada, Matsuo Sekine, Yukinobu Miki, Masahiro Okaji

    Applied Physics Letters   61 ( 8 )   967 - 969   1992.12

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    All-niobium thin-film nanobridges were fabricated with bridge sizes of 40-nm length, 50-nm width, and 100-nm thickness. We investigated the performance of the nanobridges by monitoring Shapiro steps induced on the current-voltage curves by an optically pumped far-infrared laser. These steps have been observed up to 693 GHz (433 μm). This is a twofold increase over that previously reported on thin-film nanobridges.

    DOI: 10.1063/1.108472

  • New Positive EB Resist with Strong Resistance to Plasma Damage Reviewed

    Kazuo Yamaguchi, Hiroyuki Ozaki, Akira Hirao, Nobumitsu Hirose, Yuuichi Harada, Yoshinori Uzawa, Matsuo Sekine, Shigeru Yoshimori, Mitsuo Kawamura

    Journal of the Electrochemical Society   139 ( 3 )   L33 - L34   1992.3

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    Copolymers of methyl methacrylate (MMA) and 3–triethoxysilylpropyl methacrylate (ESPMA) were synthesized and employed as an electron beam (EB) resist. The copolymer with a content of 10 mol% ESPMA worked as a positive EB resist and had 4–10 times as strong a resistance as poly(methylmethacrylate) (PMMA) to CBrF3 plasma etching. The resolution and sensitivity were almost the same as those of PMMA. From experimental results concerning the insolubility of the plasma–irradiated copolymer and measurement of IR spectra, the enhanced resistance to plasma etching appears to be caused by formation of a cross–linking structure based on the Si–O–Si linkage.

    DOI: 10.1149/1.2069330

  • Properties of all-Nb thin film microbridges fabricated by nanometer process Reviewed

    Y. Harada, N. Hirose, Y. Uzawa, M. Sekine, S. Yoshimori, M. Kawamura

    Physica C: Superconductivity and its applications   185-189 ( PART 4 )   2555 - 2556   1991.12

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    We have fabricated all-Nb thin film microbridges by using newly developed nanometer process. These microbridges show the high sensitivity of the radiation detection. We have investigated the properties of microbridges by changing the bridge-region parameters.

    DOI: 10.1016/0921-4534(91)91401-O

  • Analysis of quasiparticle injection three-terminal device Reviewed

    Yuichi Harada, Nobumitsu Hirose, Yoshinori Uzawa, Shigeru Yoshimori, Matsuo Sekine, Mitsuo Kawamura

    Infrared Physics   32 ( C )   129 - 137   1991

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    The QPI (quasiparticle injection) devices have the most transistor-like characteristics in many superconducting three-terminal devices. In particular, Quiteron which operates with the principle of suppression of the energy gap only to modulate the conductance of the output junction has a promising feature, such as a large gain, non-latching operation, and binary inversion. In this paper, we have investigated the behavior of the energy gaps to analyze the characteristics of the QPI devices. Current-voltage characteristics of QPI device is calculated by using these values of the energy gaps. First we have introduced the nonequilibrium GL equation. Then we have derived a set of equations for QPI devices by using this equation. It is found that the energy gap of middle layer has the singularity under quasiparticle injection and the QPI device may have a large gain for suitable junction resistances.

    DOI: 10.1016/0020-0891(91)90103-M

  • Characteristics of all-Nb thin film microbridges by nanometer fabrication

    Yuichi Harada, N. Hirose, Y. Uzawa, M. Sekine

    23rd International Conference on Solid State Devices and Materials - SSDM '91 Conference on Solid State Devices and Materials   520 - 522   1991

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    We have fabricated the all-Nb thin film microbridges by our developed nanometer process. These microbridges have high sensitivity of radiation and reliability. It is observed that the properties of devices change by varying the sizes of bridge-region. We have also fabricated the series arrays and observed that they operate coherently.

  • Properties of the nb thin-film nanobridges prepared by nanometer fabrication process Reviewed

    Yuichi Harada, Nobumitsu Hirose, Yoshinori Uzawa

    Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes   30 ( 12 )   3933 - 3937   1991

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    We describe the properties of Nb thin-film nanobridges fabricated by means of our original nanometer-scale process. Our original nanofabrication techniques include the synthesis of a new electron beam (EB) resist and the use of CBrF3 as an etchant for reactive ion etching (RIE). Fabricated nanobridges have high sensitivity of radiation and high reliability. It is observed that the properties of nanobridges can be changed by varying the bridge length and its thickness. We have also fabricated the series arrays and observed that they operate coherently.

    DOI: 10.1143/JJAP.30.3933

  • Microcontact Josephson triode fabricated by self-alignment process technique Reviewed

    Nobumitsu Hirose, Yuuichi Harada, Shigeru Yoshimori, Mitsuo Kawamura

    Electronics and Communications in Japan, Part II: Electronics (English translation of Denshi Tsushin Gakkai Ronbunshi)   73 ( 1 )   1 - 7   1990.1

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    A Josephson triode is a three-terminal superconductive device integrated with three Josephson devices. One of the three devices is used as a local oscillator and the triode can be used as a heterodyne detector. In such an application, since a Josephson device is used as a local oscillator, the frequency of the oscillator can be varied continuously, and the thermal noise is extremely low. However, there is no experimental report regarding the Josephson triode. In this study, microcontact Josephson triodes were fabricated by the self-alignment process technique using electron beam exposure. This device showed a negative resistance in the current-voltage characteristic of the converter junction.

  • FABRICATION OF SELF-ALIGNMENT MICRO-CONTACT JOSEPHSON JUNCTIONS. Reviewed

    Nobumitsu Hirose, Yuichi Harada, Shigeru Yoshimori, Mitsuo Kawamura

    Transactions of the Institute of Electronics and Communication Engineers of Japan. Section E   E69 ( 4 )   425 - 426   1986.4

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    We fabricated micro-contact Josephson junctions by self-alignment process, using double-layer-resist electron beam exposure and RIE. We chose NB as superconductive materials. The junctions show the Josephson effect under millimeter wave (70 GHz) radiation less than 100 mu w and the 7th Shapiro step.

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Presentations

  • Science village by DC powering Invited International conference

    Yuichi Harada and @Fumio Mura

    IEEE ICDCM 2019  2019.5 

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    Event date: 2019.5 - 2019.6

    Language:English   Presentation type:Oral presentation (general)  

    Venue:Matsue   Country:Japan  

MISC

  • The Hot Reality: Living in a +50°C World Invited International coauthorship

    Yuichi HARADA

    2024.6

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    Language:English   Publishing type:Article, review, commentary, editorial, etc. (other)  

Industrial property rights

Patent   Number of applications: 1   Number of registrations: 1
Utility model   Number of applications: 0   Number of registrations: 0
Design   Number of applications: 0   Number of registrations: 0
Trademark   Number of applications: 0   Number of registrations: 0

Professional Memberships

  • American Physical Society

    1992.6 - Present

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  • IEICE

    1988.2 - Present

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  • The Japan Society of Applied Physics

    1987.2

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  • The Japan Society of Applied Physics

  • The Institute of Electronics, Information and Communication Engineers

  • Institute of Electrical and Electronics Engineers

  • American Physical Society

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Academic Activities

  • Screening of academic papers

    Role(s): Peer review

    2024

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    Type:Peer review 

    Number of peer-reviewed articles in foreign language journals:1

  • Screening of academic papers

    Role(s): Peer review

    2023

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    Type:Peer review 

    Number of peer-reviewed articles in foreign language journals:3

  • Screening of academic papers

    Role(s): Peer review

    2022

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    Type:Peer review 

    Number of peer-reviewed articles in foreign language journals:3

  • Screening of academic papers

    Role(s): Peer review

    2021

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    Type:Peer review 

    Number of peer-reviewed articles in foreign language journals:2

  • Screening of academic papers

    Role(s): Peer review

    2020

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    Type:Peer review 

    Number of peer-reviewed articles in foreign language journals:2

  • Screening of academic papers

    Role(s): Peer review

    2019

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    Type:Peer review 

    Number of peer-reviewed articles in foreign language journals:1

  • Screening of academic papers

    Role(s): Peer review

    2018

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    Type:Peer review 

    Number of peer-reviewed articles in foreign language journals:1

  • 独立行政法人国際協力機構(JICA) 国内支援委員会委員

    Role(s): Review, evaluation

    独立行政法人国際協力機構(JICA)  2017.4 - 2019.3

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    Type:Scientific advice/Review 

  • Screening of academic papers

    Role(s): Peer review

    2017

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    Type:Peer review 

    Number of peer-reviewed articles in foreign language journals:2

    Proceedings of International Conference Number of peer-reviewed papers:2

  • Screening of academic papers

    Role(s): Peer review

    2016

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    Type:Peer review 

    Number of peer-reviewed articles in foreign language journals:2

  • Screening of academic papers

    Role(s): Peer review

    2015

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    Type:Peer review 

    Number of peer-reviewed articles in foreign language journals:2

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Research Projects

  • 国民スポーツ・生涯スポーツの普及振興に対する助成

    2023

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    Grant type:Donation

  • Mirai2.0プロジェクト

    2023

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    Grant type:Donation

  • モビリティからの脱炭素ワークショップ - 見える化とシェアリング -

    2023

    未来社会デザイン統括本部ユニット活動

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    Authorship:Principal investigator  Grant type:On-campus funds, funds, etc.

  • Clean Cold International coauthorship

    2021.12 - 2025.12

    UK 

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    Authorship:Collaborating Investigator(s) (not designated on Grant-in-Aid) 

    Developments on sustainable cooling

  • エッジ・クラウドAIサービスを用いた課題解決

    2020.12 - 2023.3

    Joint research

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    Authorship:Principal investigator  Grant type:Other funds from industry-academia collaboration

  • A breakthrough in multiple environmental control by international cocreation on Liquid Air Cooling

    Grant number:20KK0148  2020.10 - 2024.3

    Grants-in-Aid for Scientific Research  Fund for the Promotion of Joint International Research (Fostering Joint International Research (B))

    安武 大輔, 原田 裕一, 三好 悠太, 日高 功太

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    Grant type:Scientific research funding

    施設農業の生産性の制限要因群を解消するため,次世代の冷熱エネルギーLiquid Air Coolingを核とした複合環境調節に関する以下3目標に取り組む:
    目標1:暖候期植物生産に資する局所冷却による高温ストレスの回避と栄養・生殖成長の制御
    目標2:高効率CO2施用に資する精密な冷熱流制御による温室外へのCO2漏出の抑制
    目標3:超節水栽培に資する蒸発散に由来する温室内水蒸気の凝結回収利用
    これらの3目標を日本と英国の2ヶ国4機関の国際共創によって達成し,経済性も含めた実用化・普及化に向けた中期的な方針を提示することで,近年の生産性の停滞を打破できる施設農業システムの躍進(ブレークスルー)を目指す.

    CiNii Research

  • Liquid Air Coolingを核とした国際共創による複合環境調節の躍進

    2020 - 2023

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Fostering Joint International Research (B)

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    Authorship:Coinvestigator(s)  Grant type:Scientific research funding

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Educational Activities

  • Practical entrepreneurship education based on open innovation and graduate eduncation on nanotechnology and data science.

Class subject

  • 実用研究技能特論 de

    2024.10 - 2024.12   Fall quarter

  • Advanced Lecture on Research Skills Development

    2024.10 - 2024.12   Fall quarter

  • ナノ加工成長特論I

    2024.10 - 2024.12   Fall quarter

  • 実践データサイエンス入門

    2024.6 - 2024.8   Summer quarter

  • イノベーション・マネジメント

    2024.6 - 2024.8   Summer quarter

  • Nanofabrication and nanogrowth

    2023.10 - 2023.12   Fall quarter

  • Advanced Lecture on Research Skills Development

    2023.10 - 2023.12   Fall quarter

  • 実践データサイエンス入門

    2023.6 - 2023.8   Summer quarter

  • イノベーション・マネジメント

    2023.6 - 2023.8   Summer quarter

  • Advanced Lecture in Research Skills Development (English)

    2022.10 - 2022.12   Fall quarter

  • ナノ加工成長特論

    2022.10 - 2022.12   Fall quarter

  • 実用研究技能特論 de

    2022.10 - 2022.12   Fall quarter

  • 実践データサイエンス入門

    2022.6 - 2022.8   Summer quarter

  • 総合理工学修士演習

    2022.4 - 2023.3   Full year

  • 総合理工学修士実験

    2022.4 - 2023.3   Full year

  • イノベーション・マネジメント

    2022.4 - 2022.9   First semester

  • イノベーション・マネジメント

    2022.4 - 2022.9   First semester

  • Advanced Lecture in Research Skills Development (English)

    2021.10 - 2022.3   Second semester

  • 実用研究技能特論 de

    2021.10 - 2021.12   Fall quarter

  • 実践データサイエンス入門

    2021.6 - 2021.8   Summer quarter

  • 実践データサイエンス入門

    2021.6 - 2021.8   Summer quarter

  • Doctoral Research (III)

    2021.4 - 2022.3   Full year

  • イノベーション・マネジメント

    2021.4 - 2021.9   First semester

  • イノベーション・マネジメント

    2021.4 - 2021.9   First semester

  • Advanced Lecture in Research Skills Development (English)

    2020.10 - 2021.3   Second semester

  • イノベーション・マネジメント

    2020.10 - 2021.3   Second semester

  • *Practical Research Skills Development

    2020.10 - 2021.3   Second semester

  • *Nanofabrication and Nanogrowth

    2020.10 - 2021.3   Second semester

  • 実践データサイエンス入門

    2020.10 - 2020.12   Fall quarter

  • *Nanofabrication and Nanogrowth

    2019.10 - 2020.3   Second semester

  • *Practical Research Skills Development

    2019.10 - 2020.3   Second semester

  • Advanced Lecture in Research Skills Development (English)

    2019.10 - 2020.3   Second semester

  • Nanofabrication and nanogrowth(ナノ加工成長特論)

    2019.10 - 2020.3   Second semester

  • イノベーション・マネジメント

    2019.4 - 2019.9   First semester

  • イノベーション・マネジメント

    2019.4 - 2019.9   First semester

  • Advanced Lecture in Research Skills Development (English)

    2018.10 - 2019.3   Second semester

  • Nanofabrication and nanogrowth(ナノ加工成長特論)

    2018.10 - 2019.3   Second semester

  • イノベーション・マネジメント

    2018.4 - 2018.9   First semester

  • Advanced Lecture in Research Skills Development (English)

    2017.10 - 2018.3   Second semester

  • Practical research skills development

    2017.10 - 2018.3   Second semester

  • Nanofabrication and nanogrowth

    2017.10 - 2018.3   Second semester

  • Nanofabrication and nanogrowth(ナノ加工成長特論)

    2017.10 - 2018.3   Second semester

  • 工業倫理・工業経営

    2017.4 - 2017.9   First semester

  • Advanced Lecture in Research Skills Development (English)

    2016.10 - 2017.3   Second semester

  • Practical research skills development

    2016.10 - 2017.3   Second semester

  • Nanofabrication and nanogrowth

    2016.10 - 2017.3   Second semester

  • Nanofabrication and nanogrowth(ナノ加工成長特論)

    2016.10 - 2017.3   Second semester

  • 工業倫理・工業経営

    2016.4 - 2016.9   First semester

  • アントレプレナーシップII -研究・技術マネジメント論-

    2015.10 - 2016.3   Second semester

  • 工業倫理・工業経営

    2015.4 - 2015.9   First semester

  • Advanced Lecture in Research Skills Development (English)

    2024.10 - 2024.12   Fall quarter

  • ナノ加工成長特論Ⅰ

    2024.10 - 2024.12   Fall quarter

  • 実用研究技能特論 de

    2024.10 - 2024.12   Fall quarter

  • 実践データサイエンス入門

    2024.6 - 2024.8   Summer quarter

  • イノベーション・マネジメント

    2024.4 - 2024.9   First semester

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FD Participation

  • 2015.4   Role:Participation   Title:平成27年度第1回全学FD

    Organizer:University-wide

Participation in international educational events, etc.

  • 2022.11

    Kyushu University

    MIRAI2.0 Research & Innovation Week 2022

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    Venue:Japan

    Number of participants:300

Other educational activity and Special note

  • 2024  Coaching of Students' Association  GLEAP

     詳細を見る

    顧問

  • 2023  Coaching of Students' Association  GLEAP

     詳細を見る

    顧問

  • 2023  Coaching of Students' Association  QSIP

     詳細を見る

    顧問

  • 2022  Coaching of Students' Association  GLEAP

     詳細を見る

    顧問

  • 2022  Coaching of Students' Association  QSIP

     詳細を見る

    顧問

  • 2021  Coaching of Students' Association  GLEAP

     詳細を見る

    顧問

  • 2020  Coaching of Students' Association  GLEAP

     詳細を見る

    顧問

  • 2019  Coaching of Students' Association  GLEAP

     詳細を見る

    相談役

  • 2004  Special Affairs  Innovation management at University of Oxford

     詳細を見る

    Innovation management at University of Oxford

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Outline of Social Contribution and International Cooperation activities

  • Mirai project between Japan and Sweden, Renkei project between Japan and UK.
    Contribution to DX and entrepreneurship education in Nogata city based on the collaborative agreement.
    Collaborative education with Universities in Vietnam on semiconductor

Social Activities

  • アントレプレナーシップ教育

    直方市立直方西小学校  2024.2

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    Audience:Infants, Schoolchildren, Junior students, High school students

    Type:Seminar, workshop

  • 小学生へのアントレプレナーシップ教育

    直方西小学校  2023.6

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    Audience:Infants, Schoolchildren, Junior students, High school students

    Type:Seminar, workshop

  • 直方西小学校におけるアントレプレナーシップ教育

    直方市  直方西小学校  2023.2

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    Audience:General, Scientific, Company, Civic organization, Governmental agency

    Type:Other

    外国人も購入したいお店を出すことで、グループで検討を行い、英文にてプレゼンテーション資料を作成した。それを、フィンランド人に向けて、プレゼンテーションをして、高評価を得た。

  • 直方西小学校におけるアントレプレナーシップ教育

    直方市  直方西小学校  2022.2

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    Audience:General, Scientific, Company, Civic organization, Governmental agency

    Type:Other

    外国人も購入したいお店を出すことで、グループで検討を行い、英文にてプレゼンテーション資料を作成した。それを、フィンランド人に向けて、プレゼンテーションをして、高評価を得た。

  • 小学生へのアントレプレナーシップ教育

    直方西小学校  2022.2

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    Audience:Infants, Schoolchildren, Junior students, High school students

    Type:Seminar, workshop

  • アントレプレナーシップ教育

    直方西小学校  2021.2

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    Audience:Infants, Schoolchildren, Junior students, High school students

    Type:Seminar, workshop

  • 東京都立小石川中等教育学校SSH評価委員

    東京都立小石川中等教育学校  2020.3

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    Audience:Infants, Schoolchildren, Junior students, High school students

    Type:Other

  • データセンターの活用事例 -九州大学伊都キャンパス・周辺での活動-

    一般社団法人情報通信技術委員会(TTC)  芝公園電気ビル  2019.6

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    Audience:General, Scientific, Company, Civic organization, Governmental agency

    Type:Seminar, workshop

    九州大学が進めているオープンイノベーションKOINEを紹介し、その成果として「食・エネルギー・情報の地産地消に基づくスマートシティ創成」について説明した。

  • データセンター活用:産学連携と地域振興

    データセンター展  東京ビックサイト  2019.5

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    Audience:General, Scientific, Company, Civic organization, Governmental agency

    Type:Lecture

  • 糸島サイエンス・ヴィレッジの報告

    糸島市  伊都文化会館  2019.3

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    Audience:General, Scientific, Company, Civic organization, Governmental agency

    Type:Lecture

  • 東京都立小石川中等教育学校SSH評価委員

    東京都立小石川中等教育学校  2019.3

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    Audience:Infants, Schoolchildren, Junior students, High school students

    Type:Other

  • 東京都立小石川中等教育学校SSH評価委員

    東京都立小石川中等教育学校  2018.3

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    Audience:Infants, Schoolchildren, Junior students, High school students

    Type:Other

  • 東京都立小石川中等教育学校SSH評価委員

    東京都立小石川中等教育学校  2017.3

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    Audience:Infants, Schoolchildren, Junior students, High school students

    Type:Other

  • 2012-2018 神奈川県桐光学園父母会役員(2014年中学会長、2017年高校会長)

    2012

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    2012-2018 神奈川県桐光学園父母会役員(2014年中学会長、2017年高校会長)

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Media Coverage

  • 直方市と九州大学グローバルイノベーションセンターとの連携協定と、その具体的な取り組み TV or radio program

    FM ちょっくらじお  2021.6

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    直方市と九州大学グローバルイノベーションセンターとの連携協定と、その具体的な取り組み

Activities contributing to policy formation, academic promotion, etc.

  • 2023.4 - 2025.3   電子情報技術産業協会(JEITA)直流小委員会

    アドバイザー

  • 2020.10 - 2021.3   糸島市

    市政アドバイザー

  • 2016.4 - 2026.3   九州工学教育協会

    運営委員

Acceptance of Foreign Researchers, etc.

  • Acceptance period: 2016.11 - 2018.10   (Period):1 month or more

    Nationality:Slovenia

    Business entity:Japan Society for the Promotion of Science

Travel Abroad

  • 2024.5

    Staying countory name 1:Viet Nam   Staying institution name 1:Hanoi University of Science and Technology

    Staying institution name 2:Foreign Trade University

    Staying institution name 3:Ho Chi Minh University of Information Technology

  • 2023.9

    Staying countory name 1:United Kingdom   Staying institution name 1:University of Birmingham

    Staying countory name 2:Finland   Staying institution name 2:Oulu University

  • 2023.2 - 2023.3

    Staying countory name 1:United Kingdom   Staying institution name 1:University of Birmingham

  • 2019.1

    Staying countory name 1:United Kingdom   Staying institution name 1:Royal Holloway, University of London

    Staying institution name 2:Physics Department

  • 2015.9

    Staying countory name 1:United Kingdom   Staying institution name 1:National Physical Laboratory

    Staying countory name 2:United Kingdom   Staying institution name 2:Royal Holloway, University of London

    Staying countory name 3:United Kingdom   Staying institution name 3:University of Lancaster

  • 1992.4 - 1994.3

    Staying countory name 1:Sweden   Staying institution name 1:Chalmers University of Technology

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