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arXiv · 1601.03990

Read-Green resonances in a topological superconductor coupled to a bath

Pieter W. Claeys·Stijn De Baerdemacker·Dimitri Van Neck
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Abstract

We study a topological superconductor capable of exchanging particles with an environment. This additional interaction breaks particle-number symmetry and can be modelled by means of an integrable Hamiltonian, building on the class of Richardson-Gaudin pairing models. The isolated system supports zero-energy modes at a topological phase transition, which disappear when allowing for particle exchange with an environment. However, it is shown from the exact solution that these still play an important role in system-environment particle exchange, which can be observed through resonances in low-energy and -momentum level occupations. These fluctuations signal topologically protected Read-Green points and cannot be observed within traditional mean-field theory.

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Pieter W. Claeys, Stijn De Baerdemacker, Dimitri Van Neck. 2016-06-09. Read-Green resonances in a topological superconductor coupled to a bath. https://doi.org/10.1103/physrevb.93.220503

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