Topological blocking in quantum quench dynamics

Kells, G and Sen, D and Slingerland, JK and Vishveshwara, S (2014) Topological blocking in quantum quench dynamics. In: PHYSICAL REVIEW B, 89 (23).

PDF phy_rev_89_23_2014.pdf - Published Version Restricted to Registered users only Download (923kB) | Request a copy

Abstract

We study the nonequilibrium dynamics of quenching through a quantum critical point in topological systems, focusing on one of their defining features: ground-state degeneracies and associated topological sectors. We present the notion of ``topological blocking,'' experienced by the dynamics due to a mismatch in degeneracies between two phases, and we argue that the dynamic evolution of the quench depends strongly on the topological sector being probed. We demonstrate this interplay between quench and topology in models stemming from two extensively studied systems, the transverse Ising chain and the Kitaev honeycomb model. Through nonlocal maps of each of these systems, we effectively study spinless fermionic p-wave paired topological superconductors. Confining the systems to ring and toroidal geometries, respectively, enables us to cleanly address degeneracies, subtle issues of fermion occupation and parity, and mismatches between topological sectors. We show that various features of the quench, which are related to Kibble-Zurek physics, are sensitive to the topological sector being probed, in particular, the overlap between the time-evolved initial ground state and an appropriate low-energy state of the final Hamiltonian. While most of our study is confined to translationally invariant systems, where momentum is a convenient quantum number, we briefly consider the effect of disorder and illustrate how this can influence the quench in a qualitatively different way depending on the topological sector considered.

Item Type:	Journal Article
Publication:	PHYSICAL REVIEW B
Additional Information:	copyright of this article belongs to AMER PHYSICAL SOC, USA
Department/Centre:	Division of Physical & Mathematical Sciences > Centre for High Energy Physics
Date Deposited:	19 Aug 2014 10:48
Last Modified:	19 Aug 2014 10:48
URI:	http://eprints.iisc.ac.in/id/eprint/49587

Actions (login required)

View Item