Long-range level correlations in quantum systems with finite Hilbert space dimension

We study the spectral statistics of quantum systems with finite Hilbert spaces. We derive a theorem showing that eigenlevels in such systems cannot be globally uncorrelated, even in the case of fully integrable dynamics, as a consequence of the unfolding procedure. We provide an analytic expression...

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Detalles Bibliográficos
Autores: Corps, Angel L., Relaño Pérez, Armando
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/8271
Acceso en línea:https://hdl.handle.net/20.500.14352/8271
Access Level:acceso abierto
Palabra clave:536
Power spectrum analysis
Statistics
Integrability
Chaos
Thermalization
Repulsion
Particle
Number
Model
Termodinámica
2213 Termodinámica
Descripción
Sumario:We study the spectral statistics of quantum systems with finite Hilbert spaces. We derive a theorem showing that eigenlevels in such systems cannot be globally uncorrelated, even in the case of fully integrable dynamics, as a consequence of the unfolding procedure. We provide an analytic expression for the power spectrum of the delta(n) statistic for a model of intermediate statistics with level repulsion but independent spacings, and we show both numerically and analytically that the result is spoiled by the unfolding procedure. Then, we provide a simple model to account for this phenomenon, and test it by means of numerics on the disordered XXZ chain, the paradigmatic model of many-body localization, and the rational Gaudin-Richardson model, a prototypical model for quantum integrability.