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arXiv · 2407.12750

Hidden time-reversal in driven XXZ spin chains: exact solutions and new dissipative phase transitions

Mingxing Yao·Andrew Lingenfelter·Ron Belyansky·David Roberts·Aashish A. Clerk
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Abstract

We show that several models of interacting XXZ spin chains subject to boundary driving and dissipation possess a subtle kind of time-reversal symmetry, making their steady states exactly solvable. We focus on a model with a coherent boundary drive, showing that it exhibits a unique continuous dissipative phase transition as a function of the boundary drive amplitude. This transition has no analogue in the bulk closed system, or in incoherently driven models. We also show the steady state magnetization exhibits a surprising fractal dependence on interaction strength, something previously associated with less easily measured infinite-temperature transport quantities (the Drude weight). Our exact solution also directly yields driven-dissipative double-chain models that have pure, entangled steady states that are also current carrying.

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Mingxing Yao, Andrew Lingenfelter, Ron Belyansky, David Roberts, Aashish A. Clerk. 2024-07-17. Hidden time-reversal in driven XXZ spin chains: exact solutions and new dissipative phase transitions. https://doi.org/10.1103/physrevlett.134.130404

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