Lee Hsun Lecture Series

Topic: Berry phase effects on electronic properties

Speaker: Prof. Niu Qian

　　　　Department of Physics, University of Texas, Austin

　　　  International Center for Quantum Materials, Peking University, Beijing, China

Time: 10:00-11:30 AM., Tue., Jul. 23th, 2013

Venue: Room 403, Shi Changxu Building, IMR CAS

Welcome to attend!

Abstract：

Berry curvature and orbital moment of the Bloch state are two basic ingredients, in addition to the band energy, that must be included in the formulation of semiclassical dynamics of electrons in crystals, in order to give proper account of thermodynamic and transport properties to first order in the electromagnetic field. These quantities are gauge invariant and have direct physical significance as demonstrated by numerous applications in recent years. Generalization to the case of degenerate bands has also been achieved, with important applications in spin-dependent transport. We have now extended the theory to second order in electromagnetic fields, keeping the structure of the first order theory but greatly expanding the scope of applications. I will illustrate two applications of the extended theory, magneto polarization and nonlinear anomalous Hall effects.