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arXiv · 1606.06359

Boundary-induced dynamics in 1D topological systems and memory effects of edge modes

Yan He·Chih-Chun Chien
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Abstract

Dynamics induced by a change of boundary conditions reveals rate-dependent signatures associated with topological properties in one-dimensional Kitaev chain and SSH model. While the perturbation from a change of the boundary propagates into the bulk, the density of topological edge modes in the case of transforming to open boundary condition reaches steady states. The steady-state density depends on the transformation rate of the boundary and serves as an illustration of quantum memory effects in topological systems. Moreover, while a link is physically broken as the boundary condition changes, some correlation functions can remain finite across the broken link and keep a record of the initial condition. By testing those phenomena in the non-topological regimes of the two models, none of the interesting signatures of memory effects can be observed. Our results thus contrast the importance of topological properties in boundary-induced dynamics.

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Yan He, Chih-Chun Chien. 2016-06-20. Boundary-induced dynamics in 1D topological systems and memory effects of edge modes. https://doi.org/10.1103/physrevb.94.024308

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