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arXiv · 2603.20091

Symmetric Resourceful Steady States via Non-Markovian Dissipation

Baptiste Debecker·Eduardo Serrano-Ensástiga·Thierry Bastin·François Damanet·John Martin
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Abstract

We prove a no-go theorem for symmetry-based dissipative engineering of collective-spin steady states: in spin-only Lindblad dynamics with jump operators linear in the collective-spin operators, any unique steady state exhibiting at least $\mathbb{Z}_2 \times \mathbb{Z}_2$ symmetry is necessarily the maximally mixed state. We then show that bath memory lifts this obstruction, enabling unique entangled steady states with a prescribed symmetry and a metrological gain, and providing a steady-state witness of non-Markovianity. Notably, this framework is largely insensitive to the microscopic details of the bath.

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Baptiste Debecker, Eduardo Serrano-Ensástiga, Thierry Bastin, François Damanet, John Martin. 2026-03-20. Symmetric Resourceful Steady States via Non-Markovian Dissipation. https://arxiv.org/abs/2603.20091

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