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arXiv · 2604.18244

Quantum many-body scars in random unitary circuits

Luca Capizzi·Benoît Ferté
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Abstract

Quantum many-body scars are rare exceptions to thermalization: they sustain non-thermal stationary states without the protection of any local conservation law, and are generally expected to be fragile. Here we construct an analytically tractable random unitary circuit hosting a single scar, and derive from first principles the thermalization mechanism governing perturbations thereof - described by a picture of fluctuating interfaces. Surprisingly, despite being thermodynamically irrelevant for local observables, the scar leaves a sharp fingerprint in the entanglement dynamics, driving a transition as a function of perturbation strength that is not probed by any local measurement.

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Luca Capizzi, Benoît Ferté. 2026-04-20. Quantum many-body scars in random unitary circuits. https://arxiv.org/abs/2604.18244

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