Topological signatures in a weakly dissipative Kitaev chain of finite length

Antonio D'Abbruzzo; Davide Rossini

doi:10.1103/physrevb.104.115139

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arXiv · 2106.15111

Topological signatures in a weakly dissipative Kitaev chain of finite length

Antonio D'Abbruzzo·Davide Rossini

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Abstract

We construct a global Lindblad master equation for a Kitaev quantum wire of finite length, weakly coupled to an arbitrary number of thermal baths, within the Born-Markov and secular approximations. We find that the coupling of an external bath to more than one lattice site generates quantum interference effects, arising from the possibility of fermions to tunnel through multiple paths. In the presence of two baths at different temperatures and/or chemical potentials, the steady-state particle current can be expressed through the Landauer-Büttiker formula, as in a ballistic transport setup, with the addition of an anomaly factor associated with the presence of the $p$-wave pairing in the Kitaev Hamiltonian. Such a factor is affected by the ground-state properties of the chain, being related to the finite-size equivalent of its Pfaffian topological invariant.

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Antonio D'Abbruzzo, Davide Rossini. 2021-09-21. Topological signatures in a weakly dissipative Kitaev chain of finite length. https://doi.org/10.1103/physrevb.104.115139

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