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arXiv · 2212.05346

Dissipative stabilization of entangled qubit pairs in quantum arrays with a single localized dissipative channel

Jacopo Angeletti·Stefano Zippilli·David Vitali
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Abstract

We study the dissipative stabilization of entangled states in arrays of quantum systems. Specifically, we are interested in the states of qubits (spin-1/2) which may or may not interact with one or more cavities (bosonic modes). In all cases only one element, either a cavity or a qubit, is lossy and irreversibly coupled to a reservoir. When the lossy element is a cavity, we consider a squeezed reservoir and only interactions which conserve the number of cavity excitations. Instead, when the lossy element is a qubit, pure decay and a properly selected structure of XY-interactions are taken into account. We show that in all cases, in the steady state, many pairs of distant, non-directly interacting qubits, which cover the whole array, can get entangled in a stationary way, by means of the interplay of dissipation and local interactions.

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Jacopo Angeletti, Stefano Zippilli, David Vitali. 2022-12-10. Dissipative stabilization of entangled qubit pairs in quantum arrays with a single localized dissipative channel. https://doi.org/10.1088/2058-9565%2Facd4e3

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