报告人：Xiangrong Wang

报告题目：Skyrmion Size in Skyrmion Crystals

报告摘要：A magnetic skyrmion can be in an isolated form or in a condensate form. Each skyrmion in a condensed phase takes a stripe shape at low skyrmion density and a circular shape at high skyrmion density. Skyrmions at high density form a skyrmion crystal (SkX). In this talk, we will see that skyrmion size in a SkX has a different parameter dependence as those for isolated skyrmions and stripes. A size formula and a good spin profile for skyrmions in SkXs are proposed. These findings have important implications in searching for stable smaller skyrmions at the room temperature.

报告简介：Professor Wang obtained his BA degree (1980) from Wuhan University and his ScM (1986) and PhD (1990) degrees from University of Rochester. He was awarded Minnesota Supercomputer Institute Fellow (1991) for post-doctoral studies at the University of Minnesota. He joined the Physics Department of HKUST in 1992. Professor Wang is interested in revealing the physics principles behind the novel physics phenomena in condensed matter physics. Currently, he is working on the interplay of charges, spins, and phonons in interesting materials and devices. One particular question is how the interactions of charge, spin, and phonons affect the spin dynamics and electron transport. The current research topics include magnetic domain wall motion under electric and magnetic fields, thermal gradient, and spin current of electrons and magnons; domain wall pinning theory; theories for large magnetoresistance in nonmagnetic systems; and electronic properties of novel systems. https://physics.ust.hk/eng/people_detail.php?id=22&pplcat=1