Absence of hysteresis at the Mott-Hubbard metal-insulator transition in infinite dimensions

TL;DR

This study uses high-precision Quantum Monte Carlo simulations to show that the Mott-Hubbard transition in an infinite-dimensional Hubbard model is continuous without hysteresis, challenging previous claims of a discontinuous transition.

Contribution

The paper provides the first high-precision evidence that the Mott-Hubbard transition in infinite dimensions is continuous, without hysteresis, down to very low temperatures.

Findings

Hysteresis disappears below T_{IPT} pprox 0.022W.

Transition is continuous down to T=0.325T_{IPT}.

Fermi liquid breaks down before the gap opens.

Abstract

The nature of the Mott-Hubbard metal-insulator transition in the infinite-dimensional Hubbard model is investigated by Quantum Monte Carlo simulations down to temperature T=W/140 (W=bandwidth). Calculating with significantly higher precision than in previous work, we show that the hysteresis below T_{IPT}\simeq 0.022W, reported in earlier studies, disappears. Hence the transition is found to be continuous rather than discontinuous down to at least T=0.325T_{IPT}. We also study the changes in the density of states across the transition, which illustrate that the Fermi liquid breaks down before the gap opens.