Doped Mott insulator as the origin of heavy Fermion behavior in LiV2O4

TL;DR

This study combines advanced computational methods to reveal that the heavy fermion behavior in LiV2O4 originates from a lightly doped Mott insulator state in the a1g band, aligning with experimental observations.

Contribution

It demonstrates that the heavy fermion behavior in LiV2O4 arises from a lightly doped Mott insulator, providing a microscopic understanding through combined LDA and DMFT calculations.

Findings

The a1g band in LiV2O4 is a lightly doped Mott insulator.

A sharp quasiparticle peak appears just above the Fermi level at low temperatures.

Results are consistent with recent photoemission experiments.

Abstract

We investigate the electronic structure of LiV2O4, for which heavy fermion behavior has been observed in various experiments, by the combination of the local density approximation and dynamical mean field theory. To obtain results at zero temperature, we employ the projective quantum Monte Carlo method as an impurity solver. Our results show that the strongly correlated a1g band is a lightly doped Mott insulator which -at low temperatures- shows a sharp (heavy) quasiparticle peak just above the Fermi level, which is consistent with recent photoemission experiment by Shimoyamada et al. [Phys. Rev. Lett. 96 026403 (2006)].