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arXiv · 1603.03166

Topological and dynamical properties of a generalized cluster model in one dimension

Abstract

We study the ground-state phase diagram and dynamics of the one-dimensional cluster model with several competing interactions. Paying particular attention to the relation between the entanglement spectrum (ES) and the bulk topological (winding) number, we first map out the ground-state phases of the model and determine the universality classes of the transitions from the exact solution. We then investigate the dynamical properties during interaction sweeps through the critical points of topological phase transitions. When the sweep speed is slow, the correlation functions and the entanglement entropy exhibit spatially periodic structures. On top of this, the levels in the ES oscillate temporally during the dynamics. By explicitly calculating the above quantities for excited states, we attribute these behaviors to the Bogoliubov quasiparticles generated near the critical points. We also show that the ES reflects the strength of the Majorana correlation even for the excited states.

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Takumi Ohta, Shu Tanaka, Ippei Danshita, Keisuke Totsuka. 2016-03-10. Topological and dynamical properties of a generalized cluster model in one dimension. https://doi.org/10.1103/physrevb.93.165423

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