Non-ergodic delocalized phase with Poisson level statistics

Weichen Tang; Ivan M. Khaymovich

doi:10.22331/q-2022-06-09-733

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arXiv · 2112.09700

Non-ergodic delocalized phase with Poisson level statistics

Weichen Tang·Ivan M. Khaymovich

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Abstract

Motivated by the many-body localization (MBL) phase in generic interacting disordered quantum systems, we develop a model simulating the same eigenstate structure like in MBL, but in the random-matrix setting. Demonstrating the absence of energy level repulsion (Poisson statistics), this model carries non-ergodic eigenstates, delocalized over the extensive number of configurations in the Hilbert space. On the above example, we formulate general conditions to a single-particle and random-matrix models in order to carry such states, based on the transparent generalization of the Anderson localization of single-particle states and multiple resonances.

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BibTeX RIS

Weichen Tang, Ivan M. Khaymovich. 2021-12-17. Non-ergodic delocalized phase with Poisson level statistics. https://doi.org/10.22331/q-2022-06-09-733

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