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arXiv:2307.14122 · Physical review. B./Physical review. B

Exactly solvable dynamics and signatures of integrability in an infinite-range many-body Floquet spin system

Harshit Sharma, Udaysinh T. Bhosale

Published Jan 12, 2024• 6 citations
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Abstract

We study $N$ qubits having infinite-range Ising interaction and subjected to a periodic pulse of an external magnetic field. We analytically solve the cases of $N=5$ to 11 qubits, finding its eigensystem, the dynamics of the entanglement for various initial states, and the unitary evolution operator. These quantities shows signatures of quantum integrability. For the general case of $N>11$ qubits, we provide a conjecture on quantum integrability based on the numerical evidence such as degenerate spectrum, and the exact periodic nature of the time-evolved unitary evolution operator and the entanglement dynamics. Using linear entropy, we show that for the class of initial unentangled state, the entanglement periodically displays maximum and zero values.

DOI
10.1103/physrevb.109.014412

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