Welcome to Ozawa group at Advanced Institute for Materials Research (AIMR) in Tohoku University!
We are a theoretical physics research group, studying an intersection between condensed matter physics and atomic, molecular, and optical physics.

The group The group in April, 2023
You can also see the group photo of April 2022.

What's new

  • March 1, 2024: Bruno's collaboration with experimentalists on quantum metrology is accepted for publication in National Science Review!
  • February 9, 2024: The paper on a charged particle in a two-dimensional lattice under an imaginary magnetic field is published in Physical Review B! Phys. Rev. B 109, 085113 (2024)
  • February 1, 2024: Tomoki selected as the recipient of the 6th Teruo Hiruma Optical Science Award by Research Foundation for Opto-Science and Technology!
  • January 17, 2024: Ryo's collaboration on non-Hermitian skin effect under nonsymmorphic symmetries is published in Physical Review B! Phys. Rev. B 109, 035131 (2024)
  • January 9, 2024: The paper in which we studied properties of a discrete nonlinear Schrödinger equation coupled to density-dependent gauge field is now published in Physical Review Letters! Phys. Rev. Lett. 132, 023401 (2024)
  • November 24, 2023: Ryo's collaboration with Osaka, Kyoto, Shinshu, and Titech on surface plasmon polaritons is now published as two papers in Physical Review Research 5, L042027 (2023) and Physical Review B 108, 174105 (2023)!
  • November 22, 2023: We succeeded in characterizing the many-body localization using a geometrical property of quantum states called many-body quantum metric. You can read the paper on arXiv! arXiv:2311.12280
  • October 19, 2023: Tomoki attended "2023 Asian Young Scientist Fellowship Annual Conference" held at the University of Hong Kong to receive the Asian Young Scientist Fellowship as one of the 12 inaugural fellows. You can find an article on the event here: https://www.hku.hk/press/news_detail_26709.html
  • October 13, 2023: Collaboration with Aalto University on the relation between Drude weight and many-body quantum metric is now published in Physical Review B as a Letter! Phys. Rev. B 108, L140503 (2023)
  • September 29, 2023: We propose how to detect the winding number in driven-dissipative setups, especially in the context of synthetic frequency dimensions. The paper is now on arXiv! arXiv:2309.16101
  • August 28, 2023: Our works on quantum metric in Chern insulators are highlighted in the website of the institute! Two-dimensional Chern insulators: Expanding perspectives towards graphene
  • August 25, 2023: Collaboration with Urbana and Birmingham groups on the measurement of non-Hermitian adiabatic complex Berry phase is now published in Physical Review Research! Phys. Rev. Research 5, L032026 (2023)
  • August 12, 2023: Paper on topological Stiefel-Whitney and Euler insulators is published in Physical Review B! Phys. Rev. B 108, 075129 (2023)
  • August 1, 2023: Collaboration with an experimental group in Chili on topological waveguide lattices is published in APL Photonics! APL Photonics 8, 080801 (2023)
  • July 29, 2023: Experimental collaboration with Urbana and Birmingham groups on mechanical metamaterial is published in Physical Review A! Phys. Rev. A 108, 012221 (2023)
  • July 28, 2023: Together with Tomoya Hayata from Keio University, we wrote a paper on two-dimensional lattices with an imaginary magnetic field. The paper is on arXiv now! arXiv:2307.14635
  • July 20, 2023: Together with Päivi Törmä and Grazia Salerno from Aalto University, we studied relations between superfluidity and many-body quantum metric in one-dimensional Bose systems. The paper is now on arXiv! arXiv:2307.10012
  • July 7, 2023: We studied properties of a discrete nonlinear Schrödinger equation coupled to density-dependent gauge field. The paper is now on arXiv! arXiv:2307.02952
  • June 27, 2023: Enrico's paper (collaboration with Illinois and Birmingham groups) on nonlinear dynamics of non-Hermitian dimers is published in Physical Review E! Phys. Rev. E 107, 064211 (2023)
  • June 16, 2023: Ryo's collaboration paper on non-Hermitian skin effect under nonsymmorphic symmetries is now on arXiv! arXiv:2306.08923
  • May 4, 2023: Tomoki becomes an inaugural 2023 Fellow of the Asian Young Scientist Fellowship!
  • April 30, 2023: Bruno left the group to become Junior Researcher with FCT CEEC grant at Instituto de Telecomunicações in Lisbon, Portugal!
  • April 17, 2023: We investigated the bulk-edge correspondence of Stiefel-Whitney and Euler insulators through entanglement spectrum. The paper is now on arXiv! arXiv:2304.06974
  • April 4, 2023: We proved uniqueness of the lowest Landau level. If you are curious what this means, check out our paper on arXiv! arXiv:2304.00866
  • April 3, 2023: Sana joined as a new secretary of our group!
  • February 8, 2023: Enrico's paper on nonlinear dynamics of a non-Hermitian system is now on arXiv! arXiv:2302.03572
  • January 13, 2023: Collaboration with an experimental group in Chili on topological waveguide lattices is now on arXiv! arXiv:2301.04189
  • January 5, 2023: Tomoki joined the Editorial Board of Physical Review A!
  • December 21, 2022: Our paper on singular connection approach to resonant optical responses is published in Physical Review B! Phys. Rev. B 106, 245134 (2022)
  • December 13, 2022: Bruno's paper on Laughlin states under strong geometry deformation is published in Communications in Mathematical Physics! Commun. Math. Phys. (2022)
  • November 3, 2022: Bruno's paper on quantum metric of degenerate bands is published in Physical Review B! Phys. Rev. B 106, 165133 (2022)
  • October 26, 2022: Ryo's collaboration paper on surface plasmon is now on arXiv! arXiv:2210.13637
  • October 25, 2022: We proposed a model in which non-Hermitian topological energy spectrum is induced by inter-particle interactions, and the paper is now published in Physical Review Letters! Phys. Rev. Lett. 129, 180401 (2022)
  • October 14, 2022: A paper in which we propose a connection alternative to the Berry connection, which we call the singular connection, is now on arXiv! We discuss its relation to optical transitions and the shift vector. arXiv:2210.06844
  • October 11, 2022: Enrico joined the group as a Visiting Scientist. He is a PhD student from the University of Birmingham. Welcome, Enrico!
  • October 4, 2022: Bruno's new paper on information geometry is published in Physical Review B! Phys. Rev. B 106, 155101 (2022)
  • June 2, 2022: Bruno's collaboration paper with experimentalists on topology and quantum metrology is on arXiv! arXiv:2206.00546
  • May 20, 2022: Bruno's paper on the model complexity in statistical manifolds is published in IEEE Transactions on Information Theory!
  • May 20, 2022: A paper on band structures under periodic non-Hermitian potentials is publisihed in Physical Review B! Phys. Rev. B 105, 174108 (2022)
  • May 18, 2022: Bruno's new paper on quantum metric of degenerate bands is now on arXiv: arXiv:2205.07900
  • May 12, 2022: A paper on measurement of Quantum Fisher information is published in npj Quantum Information. The experiment is done in Huazhong University of Science and Technology.
  • May 6, 2022: A paper on the measurement of the adiabatic non-Hermitian Berry phase is now on arXiv! This work is a collaboration with Gadway group from UIUC and Price group from Birmingham. arXiv:2205.02700
  • April 18, 2022: Research of the group is featured in this month's issue of a Japanese magazine Yano E plus.
  • April 1, 2022: Ryo and Greta joined the group! Bill and Bruno finally arrived at Japan to properly join the group! Welcome all!
    Here is the full member list of the group.
  • March 31, 2022: Ken left the group to become Postdoctoral Researcher at RIKEN!
  • March 2, 2022: New paper on band structures under periodic non-Hermitian potentials is on arXiv: arXiv:2203.00247
  • February 1, 2022: Bruno joined the group. Welcome Bruno!
  • January 31, 2022: Experimental collaboration on the realization of synthetic dimensions in silicon photonics has been published in Science Advances!
    Press Release from Universities (in Japanese): Yokohama National University; Tohoku University; University of Tokyo; Keio University
    Press Release in Other Media: EurekAlert!; Phys.org; SciTechDaily; Copernical; Nanowerk; Tech Explorist, etc...
    Related Media Coverage: VICE
  • January 19, 2022: Tomoki contributed a section to "Roadmap on Topological Photonics" which is now on arXiv, arXiv:2201.06315, and will be published in JPhys Photonics!
  • December 6, 2021: Ken's collaboration paper with Kyoto University on quantum walk is on arXiv: arXiv:2112.03167
  • November 15, 2021: Ken's paper is published in Phys. Rev. Research as Editor's Suggestion! Phys. Rev. Research 3, 043112 (2021)
  • September 28, 2021: A paper "Engineering geometrically flat Chern bands with Fubini-Study Kähler structure" with Bruno Mera is published in Physical Review B!
  • September 21, 2021: Tomoki wrote an article for Suri-Joshi, a website for promoting women in mathematics. "Mathematics and Physics -- Topology and Insulators and My Research Life (in Japanese)"
  • September 1, 2021: Bill joined the group. Welcome Bill!
  • August 3, 2021: Ken's new paper on nonlinear Floquet topological edge states is on arXiv: arXiv:2108.00649
  • July 21, 2021: Collaboration with Gadway group at the University of Illinois and Price group from Birmingham on synthetic mechanical lattices is now on arXiv: arXiv:2107.09649
  • July 20, 2021: New paper with Bruno Mera on Chern insulators and quantum geometry is on arXiv: arXiv:2107.09039
  • July 2, 2021: Two papers on Chern insulators and the quantum volume are published in Physical Review B!
    Phys. Rev. B 104, 045103 (2021) and Phys. Rev. B 104, 045104 (2021)
  • May 31, 2021: New paper on realization of a synthetic dimension in a silicon ring-resonator is now on arXiv: arXiv:2105.13742. This is an experimental work done in collaboration with Yokohama National University and the University of Tokyo.
  • May 19, 2021: Tomoki is now Tohoku University Distinguished Researcher!
  • May 4, 2021: A paper on topological laser published in APL Photonics
  • April 6, 2021: Tomoki receives The Young Scientists' Award, The Commendation for Science and Technology by the Minister of Education, Culture, Sports, Science and Technology!
  • April 1, 2021: Ken joined the group. Welcome Ken!
  • March 31, 2021: Feature Issue on Photonic Topological Materials in Optical Materials Express, in which Tomoki served as a guest editor, has been published online!
  • March 23, 2021: Two new papers about Chern insulators and the quantum volume are now on arXiv: arXiv:2103.11582 and arXiv:2103.11583
  • March 19, 2021: Tomoki's paper Artificial magnetic field for synthetic quantum matter without dynamical modulation has been published in Physical Review A! The paper is open access!
  • March 12, 2021: Tomoki receives 15th (2021) Young Scientist Award of the Physical Society of Japan (Division 1)!
  • January 14, 2021: Research of Tomoki has been featured in an Israeli popular magazine "Epoch". Here is a link to a related news article from AIMR.
  • January 2021: New website launched!
  • February 2020: The group was born!