Condensed Matter Theory Seminar: Zemin Huang, University of Illinois Urbana-Champaign, “Topological gauge theory for mixed Dirac stationary states in all dimensions”

Event time: 
Wednesday, November 17, 2021 - 10:30am to 11:30am
Location: 
Online () See map
Event description: 

Topological mixed quantum states in or out of equilibrium can arise in open quantum systems. Their linear responses are generally non-quantized, even though quantized topological invariants can be defined. In this talk, following arXiv:2109.06891, I will present a real-time U(1) topological gauge field action capable of reconciling this paradoxical phenomenology. In addition to non-quantized linear responses, this action encodes quantized non-linear responses associated with mixed state topology. Also, this construction demonstrates how the physical pictures of anomaly inflow and bulk-boundary correspondence extend to non-equilibrium systems.
Host: Meng Cheng (m.cheng@yale.edu)
Please contact Taylor Dunnigan (taylor.dunnigan@yale.edu) for zoom connection information