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arXiv · 2206.09688

Correlations, long-range entanglement and dynamics in long-range Kitaev chains

Gianluca Francica·Luca Dell'Anna
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Abstract

Long-range interactions exhibit surprising features which have been less explored so far. Here, studying a one-dimensional fermionic chain with long-range hopping and pairing, we discuss some general features associated to the presence of long-range entanglement. In particular, after determining the algebraic decays of the correlation functions, we prove that a long-range quantum mutual information exists if the exponent of the decay is not larger than one. Moreover, we show that the time evolution triggered by a quantum quench between short-range and long-range regions, can be characterized by dynamical quantum phase transitions without crossing any phase boundary. We show, also, that the adiabatic dynamics is dictated by the divergence of a topological length scale at the quantum critical point, clarifying the violation of the Kibble-Zurek mechanism for long-range systems.

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Gianluca Francica, Luca Dell'Anna. 2022-06-20. Correlations, long-range entanglement and dynamics in long-range Kitaev chains. https://doi.org/10.1103/physrevb.106.155126

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