Use this URL to cite or link to this record in EThOS: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.733369
Title: Non-equilibrium dynamics of Chern insulators
Author: Caio, Marcello Davide
ISNI:       0000 0004 6497 8745
Awarding Body: King's College London
Current Institution: King's College London (University of London)
Date of Award: 2017
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Abstract:
Topological states of matter exhibit a wealth of novel properties including the exact quantisation of macroscopic observables and the presence of edge states. In this thesis, we study the non-equilibrium dynamics of a class of topological phases, known as Chern insulators. By focusing on the Haldane model, we study quenches between the topological and non-topological phases, and the dynamics induced on physical observables. A notable feature is that the Chern number, calculated for an infinite system, is unchanged under the dynamics following such a quench. However, in finite-size geometries, the initial and final Hamiltonians are distinguished by the presence or absence of edge states. We study the edge excitations and describe their impact on the dynamics of the edge currents and the magnetisation. We show that, following a quantum quench, the edge currents relax towards new steady-state values, and that there is light-cone spreading of the currents into the interior of the sample. The late-time behaviour of the edge currents, after multiple traversals of the sample, is captured by a Generalised Gibbs Ensemble. We further provide an analysis of the Hall response following a quantum quench in an isolated system, with explicit results for the Haldane model. We show that the Hall conductance is no longer related to the Chern number in the post-quench state, in contrast to the equilibrium case. We also discuss the effects of generic open boundary conditions and confinement potentials. Finally, we discuss the impact of disorder on the phases of the Haldane model, both in and out of equilibrium. We conclude with a discussion of ongoing work on the non-equilibrium dynamics of the entanglement spectrum of the Haldane model, and with prospects for further research. The results presented in Chapters 2 and 3 are published in Refs [1, 2]. The results in Chapter 4 are currently in preparation for publication [3].
Supervisor: Weber, Cedric Raphael ; Bhaseen, Miraculous Joseph Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.733369  DOI: Not available
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