Regular Article

A real-space Green’s function approach for disordered Hubbard model

¹ Humanities Science Center, Southern University of Science and Technology, Shenzhen 518055, P.R. China
² Department of Applied Physics, Xi’an University of Technology, Xi’an 710054, P.R. China

^a e-mail: liuy9@sustech.edu.cn

Received: 19 April 2020
Received in final form: 19 May 2020
Published online: 24 June 2020

Abstract

Based on the equation-of-motion approach, a real-space Green’s function method is proposed, which allows us to fully consider the disorder effect in Hubbard model. Meanwhile, we improved the decoupling scheme to obtain the quasi particle resonance peak on the Fermi energy, consistent with the DMFT method with Quantum Monte Carlo solver. After introducing the Anderson disorder into the system, the three peak structure in spectrum density still exists at intermediate regime of Coulomb interaction. However, the electronic state tends to be restricted in some small puddles in presence of on-site disorder, suggesting the Anderson localization has been introduced in the Kondo peak.