Two interacting quasiparticles above the Fermi sea

TL;DR

This paper investigates how interactions and disorder influence two quasiparticles above the Fermi sea in 2D and 3D, revealing regimes with energy-independent widths and estimating the quasiparticle mobility edge.

Contribution

It provides a numerical analysis of interaction and disorder effects on two quasiparticles, introducing insights into their energy dependence and mobility edge estimation.

Findings

Identification of a regime with energy-independent Breit-Wigner width

Dependence of width on disorder strength and system size

Estimation of the two quasiparticle mobility edge

Abstract

We study numerically the interaction and disorder effects for two quasiparticles in two and three dimensions. The dependence of the interaction-induced Breit-Wigner width on the excitation energy above the Fermi level, the disorder strength and the system size is determined. A regime is found where the width is practically independent of the excitation energy. The results allow to estimate the two quasiparticle mobility edge.