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arXiv · 2506.16533

Mott metal-insulator transition in a modified periodic Anderson model: Insights from entanglement entropy and role of short-range spatial correlations

Ankur Majumder·Sudeshna Sen
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Abstract

The Mott transition is a paradigmatic phenomenon where Coulomb interactions between electrons drive a metal-insulator phase transition. It is extensively studied within the Hubbard model, where a quantum critical transition occurs at a finite temperature second-order critical point. This work investigates the Mott transition in a modified periodic Anderson model that may be viewed as a three-orbital lattice model including an interacting, localized orbital coupled to a delocalized conduction orbital via a second conduction orbital. Within the dynamical mean field theory, this model possesses a strictly zero temperature quantum critical point separating a Fermi liquid and a Mott insulating phase. By employing a simplified version of the dynamical mean field theory, namely, the two-site or linearized dynamical mean field theory, an analytical estimate is provided for the critical parameter strengths at which the transition occurs at zero temperature. An analytical estimate of the single-site von Neumann entanglement entropy is also provided. This measure can be used as a robust identifier for the phase transition. These calculations are extended to their cluster version to incorporate short-range, spatial correlations and discuss their effects on the transition observed in this model.

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Ankur Majumder, Sudeshna Sen. 2025-06-19. Mott metal-insulator transition in a modified periodic Anderson model: Insights from entanglement entropy and role of short-range spatial correlations. https://doi.org/10.1002/adts.202501224

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