Speaker: Zhenyu Xiao Peking University
Time: 2021-11-10 19:15-2021-11-10 20:15
Venue: MMW S527 + Tencent Meeting (ID: 603 5655 1923, Password: 1984)
Altland-Zirnbauer (1997) gave ten-fold symmetry classification of disordered electron system. The localization property and critical behavior of electron is universal in a given spatial dimension and symmetry class. In the ten-fold symmetry classification, the periodic table of topological matters can be obtained. Recently, non-Hermitian systems have attracted a lot interests, e.g., optical systems with energy gain and loss, biological network. Non-Hermiticity enriches the 10-fold Altland-Zirnbauer symmetry class into the 38-fold symmetry class, and non-Hermitian periodic table of topological matters has been established by Hermitization recently. We demonstrate that the critical exponents of the length scale in non-Hermitian systems coincide with the critical exponents in the corresponding Hermitian systems with additional chiral symmetry. A remarkable consequence is superuniversality and the known knowledge in Hermitian systems can be directly transformed to non-Hermitian systems.
Xiao Zhenyu is a second-year PhD student under the supervision of Prof. Ryuichi, Shindou, in the International Center for Quantum Material, Peking University. His current interests are disordered system, topological matters, non-Hermitian system and their interplay.
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