报告题目：Instanton, Inhomogeneous Phase, and Nambu-Goldstone Mode in Chiral Magnets

主 讲 人：Masaru Hongo

单 位：伊利诺伊大学芝加哥分校

时 间：11月3日21:00

ZOOM ID：210 089 8623

密 码：123456

摘 要：

The Dzyaloshinskii-Moriya (DM) interaction, described by a term proportional to the vector product of neighboring spins, is a specific interaction for spin systems to favor inhomogeneous order. In this talk, I will present some interesting analytic results for chiral magnets (or spin systems with the DM interaction) after demonstrating how we can implement the DM interaction into the O(3) nonlinear sigma model. By considering several types of the DM interaction, I will explain various instanton solutions [1] and the inhomogeneous ground states (helical and spiral phases) together with the energy spectrum of the Nambu-Goldstone modes [2].Refs.:[1] M. Hongo, T. Fujimori, T. Misumi, M. Nitta, N. Sakai, Phys.Rev.B 101 (2020) 10, 104417[2] M. Hongo, T. Fujimori, T. Misumi, M. Nitta, N. Sakai, Phys.Rev.B 104(2021) 13, 134403.

简 介：

Dr. Masaru Hongo obtained his PhD from the University of Tokyo in 2016 and is now a postdoc at Illinois University at Chicago, USA. He has also been a postdoc at RIKEN, Japan and Keio University, Japan. His field is mostly focused on statistical mechanics and quantum field theory applied to condensed matter systems. He has published more than 15 papers in Physical Review Letters, Journal of High Energy Physics, Physical Review B, Physical Review C, Physical Review D, Physics Letters B, Journal of Statistical Physics, and Annals of Physics, with over 350 citations in total.