Relationship between single-particle excitation and spin excitation at the Mott Transition

TL;DR

This paper explores the fundamental relationship between single-particle and spin excitations at the Mott transition using advanced computational methods on Hubbard models, revealing how doping affects charge and spin dynamics.

Contribution

It provides an intuitive interpretation linking single-particle and spin excitations at the Mott transition, based on comprehensive numerical results for Hubbard models.

Findings

Spin excitation dispersion derived from single-particle excitation in zero-doping limit

Doping-induced states lose charge character approaching the Mott transition

Contrasts Mott transition features with Fermi liquid and band insulator transitions

Abstract

An intuitive interpretation of the relationship between the dispersion relation of the single-particle excitation in a metal and that of the spin excitation in a Mott insulator is presented, based on the results for the one- and two-dimensional Hubbard models obtained by using the Bethe ansatz, dynamical density-matrix renormalization group method, and cluster perturbation theory. The dispersion relation of the spin excitation in the Mott insulator is naturally constructed from that of the single-particle excitation in the zero-doping limit in both one- and two-dimensional Hubbard models, which allows us to interpret the doping-induced states as the states that lose charge character toward the Mott transition. The characteristic feature of the Mott transition is contrasted with the feature of a Fermi liquid and that of the transition between a band insulator and a metal.