Exact nonequilibrium steady states of boundary driven circuit with XYZ gates

Xin Zhang; Tomaz Prosen; Vladislav Popkov

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arXiv · 2605.17018

Exact nonequilibrium steady states of boundary driven circuit with XYZ gates

Xin Zhang·Tomaz Prosen·Vladislav Popkov

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Abstract

We obtain the exact many-body density operator of a boundary-driven XXZ quantum circuit via a spatially inhomogeneous matrix product Ansatz. The Ansatz has formally infinite bond-dimension and generalizes authors' previous construction \cite{2025XXZcircuit} for the XXZ interactions. The boundary qubits are coupled to reset quantum channels that project them toward arbitrary pure target states. We find and describe a family of relatively robust separable chiral nonequilibrium steady states (NESS), which are elliptic analogs of spin helices for the circuit, and which are particularly attractive from an experimental perspective.

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quant-ph cond-mat.stat-mech math-ph math.MP

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Xin Zhang, Tomaz Prosen, Vladislav Popkov. 2026-05-16. Exact nonequilibrium steady states of boundary driven circuit with XYZ gates. https://arxiv.org/abs/2605.17018

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