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arXiv · 2307.09482

Exact Results for a Boundary-Driven Double Spin Chain and Resource-Efficient Remote Entanglement Stabilization

Andrew Lingenfelter·Mingxing Yao·Andrew Pocklington·Yu-Xin Wang·Abdullah Irfan·Wolfgang Pfaff·Aashish A. Clerk
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Abstract

We derive an exact solution for the steady state of a setup where two $XX$-coupled $N$-qubit spin chains (with possibly non-uniform couplings) are subject to boundary Rabi drives, and common boundary loss generated by a waveguide (either bidirectional or unidirectional). For a wide range of parameters, this system has a pure entangled steady state, providing a means for stabilizing remote multi-qubit entanglement without the use of squeezed light. Our solution also provides insights into a single boundary-driven dissipative $XX$ spin chain that maps to an interacting fermionic model. The non-equilibrium steady state exhibits surprising correlation effects, including an emergent pairing of hole excitations that arises from dynamically constrained hopping. Our system could be implemented in a number of experimental platforms, including circuit QED.

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Andrew Lingenfelter, Mingxing Yao, Andrew Pocklington, Yu-Xin Wang, Abdullah Irfan, Wolfgang Pfaff, Aashish A. Clerk. 2023-07-18. Exact Results for a Boundary-Driven Double Spin Chain and Resource-Efficient Remote Entanglement Stabilization. https://doi.org/10.1103/physrevx.14.021028

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