Asymmetry between the electron- and hole-doped Mott transition in the periodic Anderson model

TL;DR

This paper investigates the doping-driven Mott transition in the periodic Anderson model, revealing a notable asymmetry between electron and hole doping, with different transition orders and underlying mechanisms.

Contribution

It uncovers the asymmetric nature of the Mott transition in the periodic Anderson model, contrasting electron and hole doping behaviors and their theoretical descriptions.

Findings

Electron-doped transition is first order with solution coexistence.

Hole-doped transition is second order involving Zhang-Rice singlet delocalization.

Asymmetry differs from single-band Hubbard model behavior.

Abstract

We study the doping driven Mott metal-insulator transition (MIT) in the periodic Anderson model set in the Mott-Hubbard regime. A striking asymmetry for electron or hole driven transitions is found. The electron doped MIT at larger U is similar to the one found in the single band Hubbard model, with a first order character due to coexistence of solutions. The hole doped MIT, in contrast, is second order and can be described as the delocalization of Zhang-Rice singlets.