Disclaimer: machine translated by DeepL which may contain errors.
Assistant Professor Kazuki Yokomizo won the 40th Inoue Research Encouragement Award
Shuichi Murakami, Professor, Tokyo Institute of Technology
Assistant Professor Kazuki Yokomizo
While a doctoral student in the Department of Physics at the Tokyo Institute of Technology, Dr. Yokomizo developed a general Bloch theory for non-Hermitian systems. In non-Hermitian systems with spatial periodicity, there was no theory to describe the energy spectrum under open boundary conditions due to a peculiar phenomenon called the non-Hermitian skin effect. Yokomizo showed that the Bloch wavenumber is complex in one-dimensional systems, and established a general method for determining the set of complex wavenumbers (generalized Brünn region) in one dimension. As a result, he found that the generalized Bruun range can have a sharp point and that it depends on the parameters of the system, which is a completely different behavior from that of Hermite systems. Furthermore, we showed that the bulk-edge correspondence of topological phases, which was thought to break down in non-Hermitian systems, can be established by using generalized Bruan domains. This result provides a basis for extending the properties of topological phases in Hermitian systems to non-Hermitian systems as well. These results have contributed greatly to the development of research on band topology in non-Hermitian physics and have been applied to various physical systems. These achievements have contributed to the development of research on band topology in non-Hermite physics and have been applied to a variety of physical systems.
After receiving his degree, Dr. Yokomizo is now working as an Assistant Professor in the Ashida Laboratory of the Department of Physics, where he is expanding his research into fields such as active matter, making full use of the results of this research.
The Rigaku-bu News, January 2024