Updated on 2026/06/19

Information

 

写真a

 
TAJIMA HIROYASU
 
Organization
Faculty of Information Science and Electrical Engineering Department of Informatics Associate Professor
School of Engineering Department of Electrical Engineering and Computer Science（Concurrent）
Graduate School of Information Science and Electrical Engineering Department of Information Science and Technology（Concurrent）
Title
Associate Professor
Homepage
External link

Research Areas

  • Natural Science / Mathematical physics and fundamental theory of condensed matter physics

Degree

  • PhD （ 2015.3 The University of Tokyo ）

Research History

  • JST  創発研究者(兼任) 

    2025.4 - Present

  • Kyushu University Faculty of Information Science and Electrical Engineering Department of Informatics Associate Professor 

    2025.4 - Present

  • JSTさきがけ兼任（革新的な量子情報処理技術基盤の創出）  さきがけ研究員 

    2020.11 - 2025.3

  • The University of Electro-Communications Graduate School of Informatics and Engineering Assistant Professor 

    2020.4 - 2025.3

  • Kyoto University 基礎物理学研究所 Specially Appointed Assistant Professor 

    2019.4 - 2020.3

  • The University of Electro-Communications  日本学術振興会 特別研究員(PD) 

    2018.4 - 2019.3

  • RIKEN  Special Postdoctoral Researcher 

    2015.4 - 2018.3

  • The University of Tokyo  日本学術振興会 特別研究員(DC1) 

    2012.4 - 2015.3

▼display all

Education

  • The University of Tokyo   大学院理学系研究科   物理学専攻　博士後期課程

    2012.4 - 2015.3

  • The University of Tokyo   大学院理学系研究科   物理学専攻　博士前期課程

    2010.4 - 2012.3

  • The University of Tokyo   理学部   物理学科

    2008.4 - 2010.3

  • The University of Tokyo   教養学部   理科一類

    2006.4 - 2008.3

Research Interests・Research Keywords

  • Research theme： resource theories

    Keyword： resource theories

    Research period： 2026

  • Research theme： Non-equilibrium physics

    Keyword： Non-equilibrium physics

    Research period： 2026

  • Research theme： Resource theory of asymmetry

    Keyword： Resource theory of asymmetry

    Research period： 2026

  • Research theme： quantum thermodynamics

    Keyword： quantum thermodynamics

    Research period： 2026

  • Research theme： quantum information theory

    Keyword： quantum information theory

    Research period： 2026

  • Research theme： quantum heat engines

    Keyword： quantum heat engines

    Research period： 2026

  • Research theme： statistical mechanics

    Keyword： statistical mechanics

    Research period： 2026

  • Research theme： information spectrum

    Keyword： information spectrum

    Research period： 2026

Awards

  • 令和8年 文部科学大臣表彰 若手科学者賞

    2026.4   対称性存在下での量子性による不可逆性抑制に関する研究

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    文部科学大臣表彰であるため

  • Young Scientist Award of the Physical Society of Japan, 2024

    2024.3   The physical society of Japan   量子ゲートおよび量子熱機関に対するコヒーレンスの影響の研究

    Hiroyasu Tajima

Papers

  • 非対称性のリソース理論の最近の発展：基礎と応用 Invited Reviewed

    Tajima Hiroyasu

    Condensed Matter Physics Summer School Lectrure Notes   4 ( 0 )   155 - 172   2026.4   （ eISSN:27582159 ）

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    Language：Japanese   Publisher：The Condensed Matter Physics Summer School Committee  

    今日、対称性は現代物理の最も重要な指導原理となっている。近年、対称性と物理学のつながりを、量子情報理論の観点から理解する研究が活発に行われている。そうした研究が土台として用いるのが、非対称性のリソース理論（Resource theory of asymmetry）と呼ばれる、量子情報理論の新興分野である。本稿では 2025 年夏の学校のテキストとして、最近の非対称性のリソース理論の発展を概観する。

    DOI： 10.57393/natsugaku.4.0_155

    CiNii Research

  • Gibbs-Preserving Operations Requiring Infinite Amount of Quantum Coherence Reviewed

    Tajima, H; Takagi, R

    Physical Review Letters   134 ( 17 )   2025.4   （ ISSN:0031-9007 eISSN:1079-7114 ）

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    Authorship：Lead author,　Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society (APS)  

    Gibbs-preserving operations have been studied as one of the standard free processes in quantum thermodynamics. Although they admit a simple mathematical structure, their operational significance has been unclear due to the potential hidden cost to implement them using an operationally motivated class of operations, such as thermal operations. Here, we show that this hidden cost can be infinite - we present a family of Gibbs-preserving operations that cannot be implemented by thermal operations aided by any finite amount of quantum coherence. Our result implies that there are uncountably many Gibbs-preserving operations that require unbounded thermodynamic resources to implement, raising a question about employing Gibbs-preserving operations as available thermodynamics processes. This finding is a consequence of the general lower bounds we provide for the coherence cost of approximately implementing a certain class of Gibbs-preserving operations with a desired accuracy. We find that our lower bound is almost tight, identifying a quantity - related to the energy change caused by the channel to implement - as a fundamental quantifier characterizing the coherence cost for the approximate implementation of Gibbs-preserving operations.

    DOI： 10.1103/PhysRevLett.134.170201

    Web of Science

    Scopus

    PubMed

    Other Link： https://link.aps.org/article/10.1103/PhysRevLett.134.170201

  • Symmetry Induced Enhancement in Finite-Time Thermodynamic Trade-Off Relations Reviewed

    Funo K., Tajima H.

    Physical Review Letters   134 ( 8 )   2025.2   （ ISSN:00319007 eISSN:1079-7114 ）

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    Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society (APS)  

    Symmetry imposes constraints on open quantum systems, affecting the dissipative properties in nonequilibrium processes. Superradiance is a typical example in which the decay rate of the system is enhanced via a collective system-bath coupling that respects permutation symmetry. Such a model has also been applied to heat engines. However, a generic framework that addresses the impact of symmetry in finite-time thermodynamics is not well established. Here, we show a symmetry-based framework that describes the fundamental limit of collective enhancement in finite-time thermodynamics. Specifically, we derive a general upper bound on the average jump rate, which quantifies the fundamental speed set by thermodynamic speed limits and trade-off relations. We identify the symmetry condition that achieves the obtained bound, and explicitly construct an open quantum system model that goes beyond the enhancement realized by the conventional superradiance model.

    DOI： 10.1103/PhysRevLett.134.080401

    Scopus

    Other Link： https://link.aps.org/article/10.1103/PhysRevLett.134.080401

  • Wigner-Araki-Yanase Theorem for Continuous and Unbounded Conserved Observables Reviewed

    Yui Kuramochi, Hiroyasu Tajima

    Physical Review Letters   131 ( 21 )   210201   2023.11   （ ISSN:0031-9007 eISSN:1079-7114 ）

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    Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society (APS)  

    The Wigner-Araki-Yanase (WAY) theorem states that additive conservation laws imply the commutativity of exactly implementable projective measurements and the conserved observables of the system. Known proofs of this theorem are only restricted to bounded or discrete-spectrum conserved observables of the system and are not applicable to unbounded and continuous observables like a momentum operator. In this Letter, we present the WAY theorem for possibly unbounded and continuous conserved observables under the Yanase condition, which requires that the probe positive operator-valued measure should commute with the conserved observable of the probe system. As a result of this WAY theorem, we show that exact implementations of the projective measurement of the position under momentum conservation and of the quadrature amplitude using linear optical instruments and photon counters are impossible. We also consider implementations of unitary channels under conservation laws and find that the conserved observable LS of the system commutes with the implemented unitary US if LS is semibounded, while US†LSUS can shift up to possibly nonzero constant factor if the spectrum of LS is upper and lower unbounded. We give simple examples of the latter case, where LS is a momentum operator.

    DOI： 10.1103/PhysRevLett.131.210201

    Web of Science

    Scopus

    PubMed

    Other Link： http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevLett.131.210201/fulltext

  • Beyond i.i.d. in the Resource Theory of Asymmetry: An Information-Spectrum Approach for Quantum Fisher Information Reviewed

    Koji Yamaguchi, Hiroyasu Tajima

    Physical Review Letters   131 ( 20 )   2023.11   （ ISSN:00319007 eISSN:1079-7114 ）

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    Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society (APS)  

    Energetic coherence is indispensable for various operations, including precise measurement of time and acceleration of quantum manipulations. Since energetic coherence is fragile, it is essential to understand the limits in distillation and dilution to restore damage. The resource theory of asymmetry (RTA) provides a rigorous framework to investigate energetic coherence as a resource to break time-translation symmetry. Recently, in the independent and identically distributed (i.i.d.) regime where identical copies of a state are converted into identical copies of another state, it was shown that the convertibility of energetic coherence is governed by a standard measure of energetic coherence, called the quantum Fisher information (QFI). This fact means that QFI in the theory of energetic coherence takes the place of entropy in thermodynamics and entanglement entropy in entanglement theory. However, distillation and dilution in realistic situations take place in regimes beyond i.i.d., where quantum states often have complex correlations. Unlike entanglement theory, the conversion theory of energetic coherence in pure states in the non-i.i.d. regime has been an open problem. In this Letter, we solve this problem by introducing a new technique: an information-spectrum method for QFI. Two fundamental quantities, coherence cost and distillable coherence, are shown to be equal to the spectral QFI rates for arbitrary sequences of pure states. As a consequence, we find that both entanglement theory and RTA in the non-i.i.d. regime are understood in the information-spectrum method, while they are based on different quantities, i.e., entropy and QFI, respectively.

    DOI： 10.1103/PhysRevLett.131.200203

    Scopus

    Other Link： http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevLett.131.200203/fulltext

  • Superconducting-like Heat Current: Effective Cancellation of Current-Dissipation Trade-Off by Quantum Coherence Reviewed

    Hiroyasu Tajima, Ken Funo

    Physical Review Letters   127 ( 19 )   190604   2021.11

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

    DOI： https://doi.org/10.1103/physrevlett.127.190604

  • Uncertainty Relations in Implementation of Unitary Operations Reviewed

    Tajima Hiroyasu, Shiraishi Naoto, Saito Keiji

    PHYSICAL REVIEW LETTERS   121 ( 11 )   110403   2018.9

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

    DOI： https://doi.org/10.1103/PhysRevLett.121.110403

  • Universal Sampling Lower Bounds for Quantum Error Mitigation Reviewed

    Ryuji Takagi, Hiroyasu Tajima, Mile Gu

    Physical Review Letters   131 ( 21 )   2023.11   （ ISSN:00319007 eISSN:1079-7114 ）

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    Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society (APS)  

    Numerous quantum error-mitigation protocols have been proposed, motivated by the critical need to suppress noise effects on intermediate-scale quantum devices. Yet, their general potential and limitations remain elusive. In particular, to understand the ultimate feasibility of quantum error mitigation, it is crucial to characterize the fundamental sampling cost - how many times an arbitrary mitigation protocol must run a noisy quantum device. Here, we establish universal lower bounds on the sampling cost for quantum error mitigation to achieve the desired accuracy with high probability. Our bounds apply to general mitigation protocols, including the ones involving nonlinear postprocessing and those yet to be discovered. The results imply that the sampling cost required for a wide class of protocols to mitigate errors must grow exponentially with the circuit depth for various noise models, revealing the fundamental obstacles in the scalability of useful noisy near-term quantum devices.

    DOI： 10.1103/PhysRevLett.131.210602

    Scopus

    Other Link： http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevLett.131.210602/fulltext

  • Fisher information matrix as a resource measure in the resource theory of asymmetry with general connected-Lie-group symmetry Reviewed

    Daigo Kudo, Hiroyasu Tajima

    Physical Review A   107 ( 6 )   2023.6   （ ISSN:24699926 eISSN:2469-9934 ）

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    Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society (APS)  

    In recent years, in quantum information theory, there has been a remarkable development in the general theoretical framework for studying symmetry in dynamics. This development, called resource theory of asymmetry, is expected to have a wide range of applications, from accurate time measurements to black-hole physics. Despite its importance, the foundation of resource theory of asymmetry still has room for expansion. An important problem is in quantifying the amount of resource. When the symmetry prescribed U(1) or R, i.e., with a single conserved quantity, the quantum Fisher information is known as a resource measure that has suitable properties and a clear physical meaning related to quantum fluctuation of the conserved quantity. However, it is not clear what is the resource measure with such suitable properties when a general symmetry prevails for which there are multiple conserved quantities. The purpose of this paper is to fill this gap. Specifically, we show that the quantum Fisher information matrix is a resource measure whenever a connected linear Lie group describes the symmetry. We also consider the physical meaning of this matrix and see which properties that the quantum Fisher information has when the symmetry is described by U(1) or R can be inherited by the quantum Fisher information matrix.

    DOI： 10.1103/PhysRevA.107.062418

    Scopus

    Other Link： http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevA.107.062418/fulltext

  • Switching the function of the quantum Otto cycle in non-Markovian dynamics: Heat engine, heater, and heat pump Reviewed

    Miku Ishizaki, Naomichi Hatano, Hiroyasu Tajima

    Physical Review Research   5 ( 2 )   2023.4   （ ISSN:26431564 eISSN:2643-1564 ）

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    Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society (APS)  

    Quantum thermodynamics explores novel thermodynamic phenomena that emerge when interactions between macroscopic systems and microscopic quantum ones go into action. Among various issues, quantum heat engines, in particular, have attracted much attention as a critical step in theoretical formulation of quantum thermodynamics and investigation of efficient use of heat by means of quantum resources. In the present paper, we focus on heat absorption and emission processes as well as work extraction processes of a quantum Otto cycle. We describe the former as non-Markovian dynamics, and thereby find that the interaction energy between a macroscopic heat bath and a microscopic qubit is not negligible. Specifically, we reveal that the interaction energy is divided into the system and the bath in a region of the short interaction time and remains negative in the region of the long interaction time. In addition, a counterintuitive energy flow from the system and the interaction energy to the hot bath occurs in another region of the short interaction time. We quantify these effects by defining an index of non-Markovianity in terms of the interaction energy. With this behavior of the interaction energy, we show that a non-Markovian quantum Otto cycle can switch functions such as an engine as well as a heater or a heat pump by controlling the interaction time with the heat bath. In particular, the qubit itself loses its energy if we shorten the interaction time, and in this sense, the qubit is cooled through the cycle. This property has a possibility of being utilized for cooling the qubits in quantum computing. We also describe the work extraction from the microscopic system to a macroscopic system like us humans as an indirect measurement process by introducing a work storage as a new reservoir.

    DOI： 10.1103/PhysRevResearch.5.023066

    Scopus

    Other Link： http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevResearch.5.023066/fulltext

  • Smooth Metric Adjusted Skew Information Rates Reviewed

    Koji Yamaguchi, Hiroyasu Tajima

    Quantum   7   1012 - 1012   2023   （ eISSN:2521-327X ）

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    Language：English   Publishing type：Research paper (scientific journal)   Publisher：Verein zur Forderung des Open Access Publizierens in den Quantenwissenschaften  

    Metric adjusted skew information, induced from quantum Fisher information, is a well-known family of resource measures in the resource theory of asymmetry. However, its asymptotic rates are not valid asymmetry monotone since it has an asymptotic discontinuity. We here introduce a new class of asymmetry measures with the smoothing technique, which we term smooth metric adjusted skew information. We prove that its asymptotic sup- and inf-rates are valid asymptotic measures in the resource theory of asymmetry. Furthermore, it is proven that the smooth metric adjusted skew information rates provide a lower bound for the coherence cost and an upper bound for the distillable coherence.

    DOI： 10.22331/Q-2023-05-22-1012

    Scopus

  • 最近の研究から 量子コヒーレンスによる流速・散逸のトレードオフの実効的無効化 Invited Reviewed

    田島裕康、布能謙

    日本物理学会誌   77 ( 9 )   621   2022.9

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    Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Research paper (other academic)  

    DOI： https://doi.org/10.11316/butsuri.77.9_621

  • Coherence cost for violating conservation laws Reviewed

    Hiroyasu Tajima, Naoto Shiraishi, Keiji Saito

    Physical Review Research   2 ( 4 )   043374   2020.12

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

    DOI： https://doi.org/10.1103/physrevresearch.2.043374

  • Universal limitations on implementing resourceful unitary evolutions Reviewed

    Ryuji Takagi, Hiroyasu Tajima

    Physical Review A   101 ( 2 )   022315   2020.2

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    Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

    DOI： https://doi.org/10.1103/physreva.101.022315

  • Efficiency versus speed in quantum heat engines: Rigorous constraint from Lieb-Robinson bound Reviewed

    Naoto Shiraishi , Hiroyasu Tajima

    PHYSICAL REVIEW E   96 ( 2 )   022138   2017.8

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    Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

    DOI： https://doi.org/10.1103/PhysRevE.96.022138

  • Finite-size effect on optimal efficiency of heat engines Reviewed

    Hiroyasu Tajima, Masahito Hayashi

    PHYSICAL REVIEW E   96 ( 1 )   012128   2017.7

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    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

    DOI： https://doi.org/10.1103/PhysRevE.96.012128

  • Quantum Jarzynski equality of measurement-based work extraction Reviewed

    Yohei Morikuni , Hiroyasu Tajima , Naomichi Hatano

    PHYSICAL REVIEW E   95 ( 3 )   032147   2017.3

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    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： https://doi.org/10.1103/PhysRevE.95.032147

  • Measurement-based formulation of quantum heat engines Reviewed

    Masahito Hayashi , Hiroyasu Tajima

    PHYSICAL REVIEW A   95 ( 3 )   032132   2017.3

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    Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

    DOI： https://doi.org/10.1103/PhysRevA.95.032132

  • Second law of information thermodynamics with entanglement transfer Reviewed

    Hiroyasu Tajima

    PHYSICAL REVIEW E   88 ( 4 )   042143   2013.10

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    Authorship：Lead author,　Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

    DOI： https://doi.org/10.1103/PhysRevE.88.042143

  • Description of Information Thermodynamics in terms of entanglement transferA New Second Law of Information Thermodynamics Using Entanglement Measure Reviewed

    Hiroyasu Tajima

    Proceedings of the 12th Asia Pacific Physics Conference   1   012129   2013.7

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    Authorship：Lead author,　Last author,　Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

    DOI： https://doi.org/10.7566/JPSCP.1.012129

  • Deterministic LOCC transformation of three-qubit pure states and entanglement transfer Reviewed

    Hiroyasu Tajima

    ANNALS OF PHYSICS   329 ( 1 )   1   2012.11

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    Authorship：Lead author,　Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

    DOI： https://doi.org/10.1016/j.aop.2012.11.001

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Presentations

  • Universal trade-off structure between symmetry, irreversibility and quantum coherence

    Hiroyasu Tajima

    26th Annual Quantum Information Processing 2023 (QIP2023)  2023.2 

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    Event date： 2023.2

    Language：English   Presentation type：Oral presentation (general)  

  • Gibbs-preserving operations requiring infinite amount of quantum coherence

    Hiroyasu Tajima

    28th Annual Quantum Information Processing 2025 (QIP2025)  2025.2 

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    Language：English   Presentation type：Oral presentation (general)  

  • Quantum geometric tensor determines the i.i.d. conversion rate in the resource theory of asymmetry for any compact Lie group

    Koji Yamaguchi, Yosuke Mitsuhashi, Tomohiro Shitara, Hiroyasu Tajima

    28th Annual Quantum Information Processing 2025 (QIP2025)  2025.2 

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    Language：English   Presentation type：Oral presentation (general)  

  • Universal tradeoff relations between resource cost and irreversibility of channels: General-resource Wigner-Araki-Yanase theorems and beyond

    Hiroyasu Tajima

    29th Annual Quantum Information Processing Conference 2026 (QIP2026)  2026.1 

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    Language：English   Presentation type：Oral presentation (general)  

  • 非対称性のリソース理論の最近の進展：基礎と応用 Invited

    田島裕康

    量子もつれと原子核物理  2025.6 

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    Event date： 2025.6

    Language：Japanese   Presentation type：Oral presentation (invited, special)  

  • A Unified Framework for Symmetry-Induced Limitations in Quantum Information Processing Invited

    Hiroyasu Tajima

    Czech-Japan Workshop on Quantum Technologies  2025.5 

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    Event date： 2025.5

    Language：English   Presentation type：Oral presentation (invited, special)  

  • Wigner-Araki-Yanase定理の発展とその周辺: 対称性がダイナミクスにもたらす普遍的制限 Invited

    田島裕康

    第10回QUATUO研究会  2024.1 

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    Event date： 2024.1

    Language：Japanese   Presentation type：Oral presentation (invited, special)  

  • Universal trade-off structure between symmetry, irreversibility and quantum coherence Invited

    Hiroyasu Tajima

    XV. International Workshop LIE THEORY AND ITS APPLICATIONS IN PHYSICS  2023.6 

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    Event date： 2023.6

    Language：English   Presentation type：Oral presentation (invited, special)  

  • 原子核における"Open" problems Invited

    田島裕康

    第４回若手放談会：エキゾチック核物理の将来  2023.3 

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    Event date： 2023.3

    Language：Japanese   Presentation type：Symposium, workshop panel (nominated)  

  • 量子開放系におけるエネルギーの流れと量子効果 Invited

    田島裕康

    第４回若手放談会：エキゾチック核物理の将来  2023.3 

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    Event date： 2023.3

    Language：Japanese   Presentation type：Oral presentation (invited, special)  

  • 熱流と量子効果の関係 Invited

    田島裕康

    最適輸送とその周辺 - 機械学習から熱力学的最適化まで  2023.3 

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    Event date： 2023.3

    Language：Japanese   Presentation type：Oral presentation (invited, special)  

  • Universal trade-off structure between symmetry, irreversibility and quantum coherence Invited

    Hiroyasu Tajima

    APS March meeting  2023.3 

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    Event date： 2023.3

    Language：English   Presentation type：Oral presentation (invited, special)  

  • Universal sampling lower bounds for quantum error mitigation Invited

    田島裕康

    NICT若手チャレンジラボ・ミニ研究会  2023.2 

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    Event date： 2023.2

    Presentation type：Oral presentation (invited, special)  

  • 量子チャンネル実装における対称性・不可逆性・量子性の統一的トレードオフ構造とその応用 Invited

    田島裕康

    量子情報と量子基礎論の諸側面  2023.2 

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    Event date： 2023.2

    Language：Japanese   Presentation type：Oral presentation (invited, special)  

  • Exploration of quantum gravity and condensed matter physics based on symmetry and information geometry

    Hiroyasu Tajima

    Extreme Universe Second Annual Meeting  2022.12 

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    Event date： 2022.12

    Language：English   Presentation type：Oral presentation (invited, special)  

  • Universal trade-off structure between symmetry, irreversibility and quantum coherence

    Hiroyasu Tajima

    quantum resources workshop  2022.12 

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    Event date： 2022.12

    Language：English   Presentation type：Oral presentation (general)  

  • Universal trade-off structure between symmetry, irreversibility and quantum coherence

    Hiroyasu Tajima

    2nd International Symposium on Trans-Scale Quantum Science (TSQS2022)  2022.11 

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    Event date： 2022.11

    Language：English   Presentation type：Oral presentation (general)  

  • Universal trade-off structure between symmetry, irreversibility and quantum coherence and its application to black hole physics

    Hiroyasu Tajima

    Quantum Extreme Universe From Quantum Information  2022.9 

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    Event date： 2022.9

    Language：English   Presentation type：Oral presentation (general)  

  • Superconducting-like heat current: Effective cancellation of current-dissipation trade off by quantum coherence

    Hiroyasu Tajima

    Stochastic Thermodyanmics III (WOST III)  2022.6 

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    Event date： 2022.5 - 2022.6

    Language：English   Presentation type：Oral presentation (general)  

  • A Universal Constraint on the Reversibility of Quantum Dynamics from Symmetry and Its Applications Invited

    Hiroyasu Tajima

    AQIS 2024 Satellite Workshop on Fundamental Aspects of Quantum Information  2024.8 

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    Language：English   Presentation type：Oral presentation (invited, special)  

  • Gibbs-preserving operations requiring infinite amount of quantum coherence Invited

    Hiroyasu Tajima

    Frontiers in Non-equilibrium Physics 2024  2024.7 

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    Language：English   Presentation type：Oral presentation (invited, special)  

  • Superconducting-like heat current: Effective cancellation of current-dissipation trade off by quantum coherence Invited

    Hiroyasu Tajima

    理研ithemsワークショップ  2022.7 

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    Language：English   Presentation type：Public lecture, seminar, tutorial, course, or other speech  

  • Universal trade-off structure between symmetry, irreversibility and quantum coherence

    Hiroyasu Tajima

    Quantum Thermodynamics 2023  2023.7 

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    Language：English   Presentation type：Oral presentation (general)  

  • Universal trade-off structure between symmetry, irreversibility and quantum coherence

    Hiroyasu Tajima

    Statphys 28  2023.8 

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    Language：English   Presentation type：Oral presentation (general)  

  • Universal limitation of quantum information recovery: symmetry versus coherence

    Hiroyasu Tajima

    APS March meeting  2022.3 

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    Presentation type：Oral presentation (general)  

  • Universal tradeoff relations between resource cost and irreversibility of channels: General-resource Wigner-Araki-Yanase theorems and beyond Invited

    Hiroyasu Tajima

    Kyoto Workshop on Quantum Thermodynamics and Stochastic Thermodynamics 2025  2025.12 

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    Language：English   Presentation type：Oral presentation (invited, special)  

  • Universal Tradeoff Relations between Resource Cost and Irreversibility of Channels: General-Resource Wigner-Araki-Yanase Theorem and Beyond Invited

    Hiroyasu Tajima

    Perspective on Time, Uncertainty and Quantum computation  2025.12 

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    Language：English   Presentation type：Oral presentation (invited, special)  

  • 対称性の下での量子コヒーレンスの定量化と,熱力学への影響 Invited

    田島裕康

    日本物理学会第80回年次大会（2025年)共催シンポジウム 情報と量子の熱力学：最適輸送から量子多体系まで  2025.9 

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    Language：Japanese   Presentation type：Symposium, workshop panel (nominated)  

  • 量子チャンネル実装における対称性・不可逆性・量子性の統一的トレードオフ構造とその応用 Invited

    田島裕康

    第1回中部量子若手ワークショップ  2023.3 

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    Language：Japanese   Presentation type：Oral presentation (invited, special)  

  • 量子ゲートおよび量子熱機関に対するコヒーレンスの影響の研究 Invited

    田島裕康

    日本物理学会 2024年春季大会  2024.3 

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    Language：Japanese   Presentation type：Oral presentation (invited, special)  

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MISC

  • 最近の研究から 量子コヒーレンスによる流速・散逸のトレードオフの実効的無効化 Invited Reviewed

    田島裕康, 布能謙

    日本物理学会誌   77 ( 9 )   2022.9

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    Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

    DOI： 10.11316/butsuri.77.9_621

Professional Memberships

  • 日本物理学会

    2010.10 - Present

Academic Activities

  • Kyoto Workshop on Quantum Thermodynamics and Stochastic Thermodynamics 2025 International contribution

    Role(s)： Planning, management, etc.,　Panel moderator, session chair, etc.,　Peer review

    京都大学基礎物理学研究所、学術変革領域B「量子エナジー革新」  2025.12

    　More details

    Type：Academic society, research group, etc. 

    Number of participants：82

  • 日本物理学会第80回年次大会（2025年） 共催シンポジウム　情報と量子の熱力学：最適輸送から量子多体系まで

    Role(s)： Planning, management, etc.,　Panel moderator, session chair, etc.

    日本物理学会, ERATO沙川情報エネルギー変換プロジェクト, 学術変革領域研究B「量子効果によるエネルギー生成／利用の革新的効率向上法の開拓と実現」  2025.9

    　More details

    Type：Competition, symposium, etc. 

  • 2024年度ERATO（沙川）・学術変革B（田島）合同合宿会議

    Role(s)： Planning, management, etc.,　Panel moderator, session chair, etc.

    2025.3

    　More details

    Type：Academic society, research group, etc. 

  • Frontiers in Non-equilibrium Physics 2024 International contribution

    Role(s)： Planning, management, etc.,　Panel moderator, session chair, etc.

    京都大学　基礎物理学研究所  2024.7

    　More details

    Type：Academic society, research group, etc. 

  • 学術変革領域B「量子エナジー革新」kick off meeting

    Role(s)： Planning, management, etc.,　Panel moderator, session chair, etc.

    電気通信大学、学術変革領域B「量子エナジー革新」  2024.5

    　More details

    Type：Academic society, research group, etc. 

Research Projects

  • Bridging Microscopic Dynamics and Quantum Process Structure: From System-Environment Models to Operational Quantum Advantages (SEMOQA) International coauthorship

    2026.3 - 2029.2

    ISPF-International collaboration awards 2025 

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    Authorship：Principal investigator  Grant type：Joint research

  • 量子効果によるエネルギー生成／利用の革新的効率向上法の開拓と実現

    Grant number：25K24771  2026.2 - 2027.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Transformative Research Areas (B)

    田島 裕康

    　 More details

    Authorship：Principal investigator  Grant type：Scientific research funding

    CiNii Research

  • 量子効果に基づくエネルギーデバイスの性能向上理論の構築

    Grant number：25K24772  2026.2 - 2027.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Transformative Research Areas (B)

    田島 裕康

    　 More details

    Authorship：Principal investigator  Grant type：Scientific research funding

    CiNii Research

  • 量子性による不可逆性抑制の幾何的普遍原理に基づく融合領域の開拓

    Grant number：JPMJFR2365  2025.4 - 2032.3

    創発的研究支援事業 

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    Authorship：Principal investigator  Grant type：Contract research

  • Development and Application of a General Theory of Asymmetry Based on Resource Theory

    Grant number：25K00924  2025.4 - 2029.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B)

    田島 裕康, 高木 隆司

    　 More details

    Authorship：Principal investigator  Grant type：Scientific research funding

    現代物理において、対称性とその破れは最も基礎的な概念の一つである。近年、この概念をリソース理論的に取り扱う非対称性のリソース理論が、非常に大きな発展を遂げている。この理論は物理の様々な分野に応用されつつあるが、基礎理論が完成しているのが非常に限定的な群で表現される対称性に限られているという問題がある。本研究計画ではこの点を解決し、物性物理をはじめとした多くの対象に応用することを目指す。

    CiNii Research

  • Pioneering and realizing innovative methods to improve the efficiency of energy gene ration/utilization through quantum effects

    Grant number：24H00830  2024.4 - 2027.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Transformative Research Areas (B)

    田島 裕康, 野口 篤史, 金澤 輝代士, 伊藤 創祐

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    Authorship：Principal investigator  Grant type：Scientific research funding

    本領域では、これまで計算や通信と言った情報分野で確認されてきた、量子効果による古典力学に従うデバイスに比べた飛躍的な性能上昇（量子優位性）がエネルギー生成・消費の分野にも存在する事を、理論的・実験的に検証することを目標としている。本総括班では、領域全体の運営・広報・領域内交流・webによる情報発信などを行う。

    CiNii Research

  • Theory of performance enhancement of energy devices based on quantum effects

    Grant number：24H00831  2024.4 - 2027.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Transformative Research Areas (B)

    田島 裕康, 布能 謙

    　 More details

    Authorship：Principal investigator  Grant type：Scientific research funding

    近年、量子力学の性質を用いて、計算やセンシングなどの様々な情報的タスクをオーダーレベルで性能向上させる「量子優位性」が確認されつつある。本計画班では、代表者・分担者が提案した量子効果による熱機関の性能の線形オーダーでの向上についての結果を発展させ、エネルギーデバイスに対する「量子優位性」の全貌を、より高次オーダーの性能向上の可能性を含めて明らかにする一般論を構築することを目的とする。合わせて、このような性能向上を活用し、理想的な熱・仕事変換効率と高出力を合わせ持つ熱機関を実験で実装するための理論提案を行う。

    CiNii Research

  • Pioneering and realizing innovative methods to improve the efficiency of energy generation/utilization through quantum effects

    Grant number：24B204  2024.4 - 2027.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Transformative Research Areas (B)

    田島 裕康

    　 More details

    Grant type：Scientific research funding

    CiNii Research

  • 量子情報幾何に基づく、対称性・不可逆性・量子性の統一的理論の構築と応用

    Grant number：JPMJPR2014  2020.11 - 2024.3

    JST戦略的創造研究推進事業「さきがけ」  JST戦略的創造研究推進事業「さきがけ」

    田島 裕康

    　 More details

    Authorship：Principal investigator  Grant type：Contract research

  • 対称性と情報幾何に基づく量子重力・量子物性の探求

    Grant number：22H05250  2022.6 - 2024.3

    科学研究費助成事業  学術変革領域研究(A) (公募研究)

    田島 裕康

    　 More details

    Authorship：Principal investigator  Grant type：Scientific research funding

    最近発見された、対称性・不可逆性・量子性の間に普遍的に成立するトレードオフ構造をさらに深めることで、量子重力及び物性理論における理解を深めることを目標とする。この定理は、対称性を守るダイナミクスと、対応する保存量の量子揺らぎの組み合わせで、どのような量子過程が実現可能で、どのようなものが不可能かを判別することが可能になっている。この定理を拡張し、量子重力および物性理論において有用な定理を複数見出すことを目指す。

    CiNii Research

  • 誤り耐性型量子コンピュータの新規手法・応用の萌芽的研究開発

    Grant number：JPMJMS2061  2020.12 - 2031.3

    ムーンショット型研究開発事業  ムーンショット型研究開発事業

    田島 裕康 (課題推進者)

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    Authorship：Principal investigator  Grant type：Contract research

  • リソース理論に基づく量子測定・操作の統一的限界

    Grant number：19K14610  2019.4 - 2023.3

    科学研究費助成事業  若手研究

    田島 裕康

    　 More details

    Grant type：Scientific research funding

    リソース理論は量子情報理論における最重要理論の一つであるエンタングルメントの理論を拡張した理論体系である。
    このリソース理論で最近着目されているのが Resource theory of asymmetryと呼ばれる理論分野である。この分野では「保存則を満たす操作」と「リソースとして『消費』できる状態」の組み合わせによって、「保存則を破る操作」をどの程度実装できるかを考える。本研究計画では、申請者らの最近の結果（Tajima et.al. PRL 2018）を発展させ、「実装される操作による保存則の破れの度合い」と「必要なリソースの量」の間に普遍的に成立するトレードオフを導く理論を構築する。

    CiNii Research

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Educational Activities

  • 基本的には学生の関心に応じて大まかな方向性を提案し、そこから絞り込みをしていく形でテーマ決めをしていく形の指導スタイルをとっています。修士の間は田島の監修能力の及ぶ範囲（＝田島が内容の価値や正誤を理解できると思える範囲）で研究を指導するが、その間も大まかな方向性の中で一緒に考え、テーマを見つけていく形をとっている。博士課程では田島の監修を段階的に減らし、博士獲得段階では自分独自の研究の流れを持ち、他者に自分の流れに沿ったテーマを提案・監修しようと思えばできる状態を目指した指導を行う。これらの際、海外研究機関とも積極的に連携し、中長期の海外滞在を積極的にアシストすることを目指している。

Class subject

  • 量子情報・計算基礎概論

    2026.4 - 2027.3   Full year

  • 【通年】情報理工学講究

    2026.4 - 2027.3   Full year

  • 【通年】情報理工学研究Ⅰ

    2026.4 - 2027.3   Full year

  • 【通年】情報理工学演習

    2026.4 - 2027.3   Full year

  • 情報理工学論述Ⅰ

    2026.4 - 2026.9   First semester

  • 情報理工学論議Ⅰ

    2026.4 - 2026.9   First semester

  • 情報理工学読解

    2026.4 - 2026.9   First semester

  • 国際科学特論Ⅱ

    2025.10 - 2025.12   Fall quarter

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Visiting, concurrent, or part-time lecturers at other universities, institutions, etc.

  • 2024  東京科学大学 

    Semester, Day Time or Duration：11月、6コマの集中講義

  • 2022  慶應義塾大学  Classification:Intensive course  Domestic/International Classification:Japan 

    Semester, Day Time or Duration：1月、6コマの集中講義

  • 2019  大阪市立大学  Classification:Intensive course  Domestic/International Classification:Japan 

    Semester, Day Time or Duration：9月、9コマの集中講義

  • 2019  京都大学  Classification:Intensive course  Domestic/International Classification:Japan 

    Semester, Day Time or Duration：11月、9コマの集中講義

Teaching Student Awards

  • 卒研発表賞

    Year and month of award：2024.4

    Classification of award-winning students：Undergraduate student   Name of award-winning student：関口恒太郎

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    卒研発表の優秀者数名に与えられる賞

  • 修論発表賞

    Year and month of award：2022.3

    Classification of award-winning students：Postgraduate student   Name of award-winning student：工藤大吾

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    修士論文発表会で、優秀とされる学生数名に贈られる賞

Other educational activity and Special note

  • 2026  Class Teacher  クラス担任　学部

    　詳細を見る

    6班のクラス担任

Outline of Social Contribution and International Cooperation activities

  • I serve as a member of organizing committee for international conferences. I am also conducting joint research with University of South-Eastern Norway, Duke University, Nanyang Technological University, and other institutions.

Media Coverage

  • 東大と電通大、熱力学的トレードオフ関係における対称性の効果を解明 Newspaper, magazine

    日経新聞（電子版）  2025.2

  • Quantum physicists just got more certain about quantum uncertainty Newspaper, magazine

    New Scientist Ltd.  New Scientist  New Scientist issue 3470 https://www.newscientist.com/article/2409067-quantum-physicists-just-got-more-certain-about-quantum-uncertainty/  2023.12

    　More details

    Author：Other 

  • Extending the uncertainty principle by using an unbounded operator Internet

    phys.org  phys.org  https://phys.org/news/2023-12-uncertainty-principle-unbounded.html  2023.12

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    Author：Other 

  • 「量子」が変える未来のエンジン 極小世界から革新か Newspaper, magazine

    日本経済新聞社  日本経済新聞  26面8段 「科学の扉」  2023.12

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    Author：Other 

  • 東大・電通大・JST、量子コンピュータのノイズ効果を抑制する量子誤り抑制法の原理的性能限界を解明 Newspaper, magazine

    日本経済新聞社  日本経済新聞（電子版）  2023.11

    　More details

    Author：Other 

  • 電通大とJST、量子系から取り出せる量子コヒーレンスの最大量を理論的に解明 Newspaper, magazine

    日本経済新聞社  日本経済新聞(電子版)  2023.11

    　More details

    Author：Other 

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Travel Abroad

  • 2026.1 - 2026.2

    Staying countory name 1：Latvia   Staying institution name 1：University of Latvia

    Staying countory name 2：Norway   Staying institution name 2：University of South-Eastern Norway

  • 2025.5

    Staying countory name 1：Czech Republic   Staying institution name 1：Czech Technical University