Building ground states of Hubbard model by time-ordered bound-pair injection

TL;DR

This paper introduces a novel method using time-ordered quantum quenches and non-Hermitian dynamics to efficiently construct ground states of the Hubbard model by injecting electron pairs from an auxiliary reservoir.

Contribution

It presents a new approach for building correlated ground states through optimal parameters and exceptional point dynamics in non-Hermitian quantum mechanics.

Findings

Optimal parameters enable perfect electron pair transfer.

Ground states can be constructed at various fillings.

Method offers an alternative way to explore ground state features.

Abstract

According to energy band theory, ground states of a normal conductor and insulator can be obtained by filling electrons individually into energy levels, without any restrictions. It fails when the electron-electron correlation is taken into account. In this work, we investigate the dynamic process of building ground states of a Hubbard model. It is based on time-ordered quantum quenches for unidirectional hopping across a central and an auxiliary Hubbard model. We find that there exists a set of optimal parameters (chemical potentials and pair binding energy) for the auxiliary system, which takes the role of electron-pair reservoir. The exceptional point dynamics in non-Hermitian quantum mechanics allows the perfect transfer of electron pair from the reservoir to the central system, obtaining its ground states at different fillings. The dynamics of time-ordered pair-filling not only provides a method for correlated quantum state engineering, but also reveals the feature of the ground state in an alternative way.