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arXiv · 1406.5960

Entanglement Spectrum in Cluster Dynamical Mean-Field Theory

Masafumi Udagawa·Yukitoshi Motome
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Abstract

We study the entanglement spectrum of the Hubbard model at half filling on a kagome lattice. The entanglement spectrum is defined by the set of eigenvalues of reduced thermal density matrix, which is naturally obtained in the framework of the dynamical mean-field theory. Adopting the cluster dynamical mean-field theory combined with continuous-time auxiliary-field Monte Carlo method, we calculate the entanglement spectrum for a three-site triangular cluster in the kagome Hubbard model. We find that the results at the three-particle sector well captures the qualitative nature of the system. In particular, the eigenvalue of the reduced density matrix, corresponding to the chiral degrees of freedom, exhibits characteristic temperature scale T_{\rm chiral}, below which a metallic state with large quasiparticle mass is stabilized. The entanglement spectra at different particle number sectors also exhibit characteristic changes around T_{\rm chiral}, implying the development of inter-triangular ferromagnetic correlations in the correlated metallic regime.

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Masafumi Udagawa, Yukitoshi Motome. 2014-06-23. Entanglement Spectrum in Cluster Dynamical Mean-Field Theory. https://doi.org/10.1088/1742-5468/2015/01/p01016

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