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arXiv · 2601.00511

Chaos and thermalization in Clifford-Floquet dynamics

Anton Kapustin·Daniil Radamovich
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Abstract

We study the ergodic properties of a unitary Floquet dynamics arising from the repeated application of a translationally-invariant Clifford Quantum Cellular Automata to an infinite system of qubits in d dimensions. One expects that if the QCA does not exhibit any periodicity, a generic initial state of qubits will thermalize, that is, approach the infinite-temperature state. We show that this is true for many classes of states, both pure and mixed. In particular, this is true for all initial states that are short-range entangled and close to the equilibrium state. We also point out a subtle distinction between weak and strong thermalization.

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Anton Kapustin, Daniil Radamovich. 2026-01-01. Chaos and thermalization in Clifford-Floquet dynamics. https://arxiv.org/abs/2601.00511

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