PIRSA:21020002

Floquet spin chains and the stability of their edge modes

Mitra, A. (2021). Floquet spin chains and the stability of their edge modes. Perimeter Institute. https://pirsa.org/21020002

Mitra, Aditi. Floquet spin chains and the stability of their edge modes. Perimeter Institute, Feb. 15, 2021, https://pirsa.org/21020002 

          @misc{ pirsa_PIRSA:21020002,
            doi = {10.48660/21020002},
            url = {https://pirsa.org/21020002},
            author = {Mitra, Aditi},
            keywords = {Condensed Matter},
            language = {en},
            title = {Floquet spin chains and the stability of their edge modes},
            publisher = {Perimeter Institute},
            year = {2021},
            month = {feb},
            note = {PIRSA:21020002 see, \url{https://pirsa.org}}
          }

Aditi Mitra

New York University (NYU)

Talk number
PIRSA:21020002
Talk Type
Subject
Abstract

In this talk I will begin by introducing symmetry protected topological (SPT) Floquet systems in 1D. I will describe the topological invariants that characterize these systems,  and highlight their differences from SPT phases arising in static systems.  I will also discuss how the entanglement properties of a many-particle wavefunction depend on these  topological invariants. I will then show that the edge modes encountered in free fermion SPTs are remarkably robust to adding interactions, even in disorder-free systems where generic bulk quantities can heat to infinite temperatures due to the periodic driving. This robustness of the edge modes to heating can be understood in the language of strong modes for free fermion SPTs, and  almost strong modes for interacting SPTs.

I will then outline a tunneling calculation for extracting the long lifetimes of these edge modes by mapping the Heisenberg time-evolution of the edge operator to dynamics of a single particle in Krylov space.