AAPPS bulletin

News and Views

The Physical Society of Japan Announces the Recipients of the 29th Outstanding Paper Award


Vol.34 (Apr) 2024 | Article no.15 2024

5 The Physical Society of Japan Announces the Recipients of the 29th Outstanding Paper Award by JPS

In recognition of important achievements toward progress in physics, the Physical Society of Japan (JPS) annually selects outstanding papers from original research articles published in the Journal of the Physical Society of Japan, Progress of Theoretical Physics, Progress of Theoretical and Experimental Physics, and JPS Conference Proceedings. The selection committee has chosen four papers for the 2024 award based on 18 nominations (for 18 papers) made by the editors of the JPS journals and representatives of the 16 divisions of the JPS.

   The 2024 award ceremony will be held at noon on September 18, 2024.

   The titles of the four selected papers, together with their citations, follow below.

Superconductivity of 2.2 K under Pressure in Helimagnet CrAs

J. Phys. Soc. Jpn. 83, 093702 (2014)

Hisashi Kotegawa, Shingo Nakahara, Hideki Tou, and Hitoshi Sugawara

Quantum-critical phenomena are one of the central issues in condensed matter physics, and research continues to progress. The authors reported for the first time that by applying relatively low pressure to CrAs, known as a helical magnetic material, a superconducting state appears with the suppression of the magnetic phase. This is the first example of superconductivity observed in a chromium-based material. It is also interesting that superconductivity appears in the vicinity of the helical magnetic phase. This result is based on the successful synthesis of high-quality crystals and the utilization of precise electrical resistance measurements under pressure. The data quality is extremely high and the paper’s overall value is even stronger when we consider that this paper introduced a clear pressure–temperature phase diagram. In addition, while similarities in phase diagrams with unconventional superconductors such as iron-based superconductors were demonstrated, this compound has differences in the dimensionality of electronic states between other materials, promoting the subsequent search for new superconducting materials and research on quantum critical phenomena. Indeed, pressure-induced superconductivity has been discovered in chromium- and manganese-based compounds having magnetic structures similar to those of CrAs, Furthermore, new physical properties of CrAs, such as quasilinear quantum magnetoresistance, were revealed. These results are noteworthy in the research of quantum critical phenomena. Therefore, this paper deserves the Outstanding Paper Award from the Physical Society of Japan.

Detection of Phase Transition via Convolutional Neural Networks

J. Phys. Soc. Jpn. 86, 063001 (2017)

Akinori Tanaka and Akio Tomiya

In recent years, machine learning has often been used in physics research. This paper presented one methodology for detecting phase transition temperatures of statistical mechanical models by machine learning using convolutional neural networks.

Since the two-dimensional Ising model targeted in this paper has an exact solution, the exact value for the phase transition temperature is also known. The authors constructed a neural network that predicts the temperature from the spin configuration and further showed that the phase transition can be detected by using the weight parameters of the neural network to define new order parameters that are different from those usually used. The obtained ferromagnetic phase transition temperatures are generally consistent with the exact solution; however, when compared to the best numerical calculations, they do not exhibit the highest accuracy.

This work is recognized as one of the early papers that demonstrated the usefulness of machine learning in physics. It is also recognized as pioneering in that it proposed a method that utilizes the weight parameters of a neural network rather than treating it as a black box. This paper has made a significant impact on subsequent research. For these reasons, this paper deserves the Outstanding Paper Award from the Physical Society of Japan.

Topological Hall Effect from Strong to Weak Coupling

J. Phys. Soc. Jpn. 87, 033705 (2018)

Kazuki Nakazawa, Manuel Bibes, and Hiroshi Kohno

This paper studies the topological Hall effect, which is an electron transport phenomenon in magnetic textures such as magnetic skyrmions. The authors applied a spin gauge field and linear response theory to calculate the Hall effect in wide parameter ranges. In the strong coupling region, the Hall effect is determined by the Berry phase of magnetic textures, as previously understood, but in the weak coupling region, the Berry phase is diluted because of spin diffusion, and the Hall effect differs strongly depending on the parameter region. This paper is important in that it provides a unified theoretical description that covers weak to strong coupling regimes. The results are not only greatly helpful for the interpretation of experiments but also deepen our understanding of the phenomenon. This is an outstanding achievement that deserves the Outstanding Paper Award of the Physical Society of Japan.

Unique Helical Magnetic Order and Field-Induced Phase in Trillium Lattice Antiferromagnet EuPtSi

J. Phys. Soc. Jpn. 88, 013702 (2019)

Koji Kaneko, Matthias D. Frontzek, Masaaki Matsuda, Akiko Nakao, Koji Munakata, Takashi Ohhara, Masashi Kakihana, Yoshinori Haga, Masato Hedo, Takao Nakama, and Yoshichika Ōnuki

This paper presents the antiferromagnetic order and field-induced magnetic structure in the rare-earth intermetallic compound EuPtSi, which possesses an urmanite-type structure. These characteristics were revealed through single-crystal neutron diffraction. Additionally, this study reports the discovery of an order that corresponds to a magnetic skyrmion lattice.

Magnetic skyrmions are vortex-like aggregates of spins, known for their topologically protected stability. This stability has led to their use in innovative magnetic storage devices. In 2009, a triple-q structure on a two-dimensional triangular lattice was observed in the chiral 3D electron system of MnSi. This structure demonstrated the topological Hall effect and garnered significant attention. Following this discovery, similar phenomena were observed in other 3d-electron compounds, leading to research focused on practical applications. However, in 2018, an unusual anomalous Hall effect was reported in the antiferromagnet EuPtSi. This finding hinted at the potential for the first magnetic skyrmion lattice in a 4f electron system. Due to the lack of microscopic observations, further verification of this phenomenon was necessary.

This paper details a microscopic study that combines various neutron diffraction techniques to investigate magnetic structures. A key finding is the significant difference in the size of the magnetic skyrmion lattices between MnSi and EuPtSi. In MnSi, the diameter of the lattice is approximately 180 Å, while in EuPtSi, it is markedly smaller, around 18 Å, an order of magnitude less. This smaller size in EuPtSi is noteworthy as it suggests a larger emergent magnetic field due to the magnetic skyrmions, which could lead to a greater topological Hall effect. Indeed, an increase in the topological Hall effect has been observed in EuPtSi.

This study is particularly groundbreaking as it is the first to microscopically capture magnetic skyrmion lattices in rare-earth compounds. It provides vital insights into the formation mechanisms and complex physical properties of these lattices. The paper’s contributions to the field, especially in guiding subsequent explorations and theoretical studies of magnetic skyrmion lattices in rare-earth compounds, are significant. It is due to these substantial contributions that this paper is deemed an outstanding accomplishment and is deserving of the JPSJ Best Paper Award.

Non-invertible topological defects in 4-dimensional \(\mathbb{Z}_2\) pure lattice gauge theory

Prog. Theor. Exp. Phys. 2022, 013B03

Masataka Koide, Yuta Nagoya, and Satoshi Yamaguchi

The generalization of the notion of symmetry in quantum field theory has been studied from various angles in recent years. In particular, the importance of expressing generalized symmetries in terms of topological defects has been realized, and at the same time the existence of 'non-invertible symmetries', which, unlike the case of groups, do not have inverse elements, has become apparent. In this paper, by extending the method of topological defects in the two-dimensional Ising model with Kramers-Wannier duality and Z2 symmetry, concrete examples of topological defects and non-invertible symmetry in four dimensions are given constructively for the first time. Specifically, in a four-dimensional Z2 lattice gauge theory with Kramers-Wannier-Wegner duality and 1-form Z2 symmetry, the topological defects associated with this duality and symmetry are derived, and their commutation relations and the existence of non-invertible symmetry are explicitly given. This paper is recognized as an achievement worthy of the Outstanding Paper Award of the Physical Society of Japan, as it has triggered a significant acceleration in the study of non-invertible symmetries in four-dimensional field theories with duality.



  1. A White Paper from the Office of National Higher Education Science Research and Innovation Policy Council, Thailand S&T Strategy. https://www.nxpo.or.th/th/frontier-research-3/

  2. N. Ratsuntia, A. Songmunnak, N. Ritjoho, T. Sanghangthum and C. Kobdej, In Study of imaging system in proton computed tomography with data acquisition from a monolithic active pixel sensor, Siam Physics Congress 2022: Carbon Neutrality (SPC 2022). J. Phys. Conf. Ser., IOP Publishing. 2431(2023), 012093 (2022). https://doi.org/10.1088/1742-6596/2431/1/012093

  3. A. Wisitsorasak, A. Shimizu, S. Sangaroon, K. Ogawa, B. Chatthong, S. Suksaengpanomrung, A. Tamman, N. Poolyarat, M. Isobe, Feasibility study of a Heavy Ion Beam Probe for the Thailand Tokamak-1. Fusion Eng. Des. 198, 114068 (2024)

  4. P. Poramapijitwat, P. Thana, P. Sukum, Y. Liangdeng, C. Kuensaen, ...D. Boonyawan, Selective Cytotoxicity of Lung Cancer Cells—A549 and H1299—Induced by Ringer’s Lactate Solution Activated by a Non‑thermal Air Plasma Jet Device, Nightingale®. Plasma Chem. Plasma Process. 43, 805–830 (2023)

  5. The Brainpower Congress, Program Management Unit for Human Resources & Institutional Development, Research and Innovation (PMU-B), Dec 18-20, 2023 (2023)

  6. M. S. Bahramy, O. J. Clark, B.-J. Yang, J. Feng, L. Bawden, J. M. Riley, I. Marković, F. Mazzola, V. Sunko, D. Biswas, S. P. Cooil, M. Jorge, J. W. Wells, M. Leandersson, T. Balasubramanian, J. Fujii, I. Vobornik, J. E. Rault, T. K. Kim, M. Hoesch, K. Okawa, M. Asakawa, T. Sasagawa, T. Eknapakul, W. Meevasana & P. D. C. King, Ubiquitous formation of bulk Dirac cones and topological surface states from a single orbital manifold in transition-metal dichalcogenides. Nat. Mater. 17(1), 21–27 (2018)

  7. G. Gitgeatpong, Y. Zhao, P. Piyawongwatthana, Y. Qiu, L. W. Harriger, N. P. Butch, T. J. Sato, and K. Matan, Nonreciprocal Magnons and Symmetry-Breaking in the Noncentrosymmetric Antiferromagnet. Phys. Rev. Lett. 119, 047201 (2017)

  8. C. Thongbai, N. Khangrang, W. Jaikla, P. Kitisri, K. Kongmali, M.W. Rhodes, S. Rimjaem, J. Saisut, S. Supasin, S. Suphakul, Development of an Undulator Magnetic Field Measurement System for the Free-Electron Laser Facility at Chiang-Mai University. Physica Status Solidi (A) Applications and Materials Science. 220(10), 2200398 (2023)

  9. W. Passatorntaschakorn, W. Khampa, W. Musikpan, C. Bhoomanee, A. Ngamjarurojana, S. Rimjaem, Atcharawon Gardchareona,c, C. Rodwihok, H. S. Kim, N. Khambunkoed, R. Supruangnet, H. Nakajima, L. Srathongsian, P. Kanjanaboos, A. Intaniwet, A. Kaewprajak, P. Kumnorkaew, F. Goubard, P. Ruankham, D. Wongratanaphisan, A novel carbon electrode for up-scaling flexible perovskite solar cells. Appl. Mater. Today. 34, 101895 (2023)

  10. For additional details, please visit: https://www.thep-center.org

Author information

Authors and Affiliations



The authors read and approved the final manuscript.

Ethics declarations

Competing interests

The authors declare that they have no competing interests.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

[Source: https://link.springer.com/article/10.1007/s43673-024-00119-5]