Speaker
Tetsuya Onogi
(Osaka University)
Description
Topological insulators in odd dimensions are characterized by topological numbers. We prove the well-known relation between the topological number given by the Chern character of the Berry curvature and the Chern-Simons level of the low energy effective action for a general class of Hamiltonians bilinear in the fermion with general U(1) gauge interactions including non-minimal couplings by an explicit calculation. A series of Ward-Takahashi identities are crucial to relate the Chern-Simons level to a winding number, which could then be directly reduced to Chern character of Berry curvature by carrying out the integral over the temporal momenta.
Authors
Tetsuya Onogi
(Osaka University)
Hidenori Fukaya
Prof.
Satoshi Yamaguchi
(Osaka University)
Dr
Xi Wu
(Ariel University)
