Many-body localization and symmetry protected topology

Event Dates: 

Thursday, April 14, 2016 - 12:00pm

CTQM Seminar Type: 

  • Related Seminar Series

Speaker Name(s): 

Norman Yao

Speaker Affiliation(s): 

University of California Berkeley

Abstract, Event Details: 

Owing to their natural isolation, quantum optical systems of atoms, ions and molecules offer an attractive platform to study out-of-equilibrium quantum dynamics and localization. Recent progress on many-body localized phases has demonstrated that they can exhibit symmetry breaking and/or topological orders in dimensions normally forbidden by Mermin-Wagner arguments. In this talk, I will describe how to coherently prepare, protect and detect symmetry protected topological order in a non-equilibrium setting. I will explore a 1D transverse-field Ising model with periodically driven two-body terms whose Floquet dynamics mirror those of the Haldane phase. Even in the presence of generic interactions, I will show that disorder leading to many-body localization prevents arbitrary heating of the system and leads to an exponential enhancement of the edge spin coherence at infinite temperature. Finally, I will describe a natural realization in a Rydberg ensemble, leveraging the blockade to controllably toggle between ferromagnetic and antiferromagnetic Ising interactions.