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

TL;DR

This paper demonstrates how a single localized dissipative element in quantum arrays can stabilize entangled pairs of qubits across the system, leveraging dissipation and local interactions for steady-state entanglement.

Contribution

It introduces a method for stabilizing entangled qubit pairs in quantum arrays using only one lossy element, applicable to cavities with squeezed reservoirs or directly decaying qubits.

Findings

Distant qubit pairs can be entangled in steady state.

Single lossy element suffices for entanglement stabilization.

Entanglement spans the entire quantum array.

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.