Alladi Ramakrishnan Hall

Engineering Floquet topological phases using periodic driving

Ranjani Seshadri

Ben Gurion University of Negev

Abstract: Topological systems - both in equilibrium and driven out of equilibrium - have been a popular topic of research for the
last several years. In this talk, I am going to use the Bernevig-Hughes-Zhang model - one of the earliest known two-dimensional
topological insulators - as an example to show how one can generate and/or manipulate topological phases using an external
perturbation that is periodic in time. In particular, I will be discussing how using an elliptically polarized light can generate phases
with topological invariants different from the equilibrium system. Moreover, the phases can be manipulated by varying the polarization
of incident light. I will also briefly discuss how one can generate higher-order topological phases using periodic driving which results
in states localized at the corners of a two-dimensional system.


References:
1. R. Seshadri, D. Sen, arXiv:2206.03473
2. R. Seshadri, A. Dutta, D. Sen, Phys Rev B 100, 115403