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arXiv · 2403.03214

Out of Time Order Correlation of the Hubbard Model with Random Local Disorder

Chakradhar Rangi·Juana Moreno·Ka-Ming Tam
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Abstract

The out of time order correlator (OTOC) serves as a powerful tool for investigating quantum information spreading and chaos in complex systems. We present a method employing non-equilibrium dynamical mean-field theory (DMFT) and coherent potential approximation (CPA) combined with diagrammatic perturbation on the Schwinger-Keldysh contour to calculate the OTOC for correlated fermionic systems subjected to both random disorder and electrons interaction. Our key finding is that random disorder enhances the OTOC decay in the Hubbard model for the metallic phase in the weak coupling limit. However, the current limitation of our perturbative solver restricts the applicability to weak interaction regimes.

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Chakradhar Rangi, Juana Moreno, Ka-Ming Tam. 2024-03-05. Out of Time Order Correlation of the Hubbard Model with Random Local Disorder. https://doi.org/10.1063/5.0206420

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