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arXiv · 2502.20002

Local ergotropy dynamically witnesses many-body localized phases

Francesco Formicola·Grazia Di Bello·Giulio De Filippis·Vittorio Cataudella·Donato Farina·Carmine Antonio Perroni
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Abstract

Many-body localization is a dynamical phenomenon characteristic of strongly interacting and disordered many-body quantum systems which fail to achieve thermal equilibrium. From a quantum information perspective, the fingerprint of this phenomenon is the logarithmic growth of the entanglement entropy over time. We perform intensive numerical simulations, applied to a paradigmatic model system, showing that the local ergotropy, the maximum extractable work via local unitary operations on a small subsystem in the presence of Hamiltonian coupling, dynamically witnesses the change from ergodic to localized phases. Within the many-body localized phase, both the local ergotropy and its quantum fluctuations slowly vary over time with a characteristic logarithmic law analogous to the behaviour of entanglement entropy. This showcases how directly leveraging local control, instead of local observables or entropies analyzed in previous works, provides a thermodynamic marker of localization phenomena based on the locally extractable work.

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Francesco Formicola, Grazia Di Bello, Giulio De Filippis, Vittorio Cataudella, Donato Farina, Carmine Antonio Perroni. 2025-02-27. Local ergotropy dynamically witnesses many-body localized phases. https://doi.org/10.1103/2z1g-rgr9

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