Ryo Takahashi

Aug 21, 2024 | link.aps.org | Ryo Takahashi |Tomoki Ozawa

In this study, we discuss a type of bulk-boundary correspondence, which holds for topological insulators and superconductors when the parity-time (PT) and/or parity-particle-hole (PC) symmetry are present. In these systems, even when the bulk topology is nontrivial, the edge spectrum is generally gapped, and thus the conventional bulk-boundary correspondence does not hold.

Nov 6, 2023 | bmccancer.biomedcentral.com | Tomoya Yokota |Sadamoto Zenda |Takeshi Kodaira |Naomi Kiyota |Yasushi Fujimoto |Koichiro Wasano | +7 more

Methods/designThis study is a multi-institutional, two-arm, open-label, randomized phase III study. The study protocol was reviewed by the Japan Clinical Oncology Group (JCOG) Protocol Review Committee and approved by as the JCOG1912 (NEW BRIDGE) in January 2021. The certificated review board approved in March 2021, and patient accrual was started at May 2021. The trial registry number is jRCTs031210100 (https://jrct.niph.go.jp/latest-detail/jRCTs031210100).

Aug 11, 2023 | link.aps.org | Ryo Takahashi |Tomoki Ozawa

We propose an unconventional bulk-edge correspondence for two-dimensional Stiefel-Whitney insulators and Euler insulators, which are topological insulators protected by the PT symmetry. We find that, although the energy spectrum under the open boundary condition is generally gapped, the entanglement spectrum is gapless when the Stiefel-Whitney or Euler class is nonzero.