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arXiv · 2510.10629

Liouvillian Exceptional Points in Quantum Brickwork Circuits

Vladislav Popkov·Mario Salerno
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Abstract

We demonstrate that Liouvillian exceptional points (LEPs), previously explored only in continuous Lindbladian dynamics, also emerge in discrete brickwork completely positive trace-preserving (CPTP) circuits. By analytically solving a minimal two-qubit brickwork model, we identify the conditions under which discrete-time LEPs arise and show that they retain the hallmark square-root eigenvalue splitting and linear-in-time sensitivity enhancement. These results establish a direct bridge between continuous non-Hermitian physics and discrete quantum-circuit architectures, opening a path toward the realization of exceptional-point-based sensing on near-term quantum processors.

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Vladislav Popkov, Mario Salerno. 2025-10-12. Liouvillian Exceptional Points in Quantum Brickwork Circuits. https://doi.org/10.1103/ksj2-w5cj

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