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arXiv · 1304.2248

Quench Dynamics of Edge States in 2-D Topological Insulator Ribbons

Aavishkar A. Patel·Shraddha Sharma·Amit Dutta
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Abstract

We study the dynamics of edge states of the two dimensional BHZ Hamiltonian in a ribbon geometry following a sudden quench to the quantum critical point separating the topological insulator phase from the trivial insulator phase. The effective edge state Hamiltonian is a collection of decoupled qubit-like two-level systems which get coupled to bulk states following the quench. We notice a pronounced collapse and revival of the Loschmidt echo for low-energy edge states illustrating the oscillation of the state between the two edges. We also observe a similar collapse and revival in the spin Hall current carried by these edge states, leading to a persistence of its time-averaged value.

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Aavishkar A. Patel, Shraddha Sharma, Amit Dutta. 2013-04-08. Quench Dynamics of Edge States in 2-D Topological Insulator Ribbons. https://doi.org/10.1140/epjb/e2013-40657-2

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