Anderson localization of elementary excitations in disordered binary Bose mixtures: Effects of the Lee-Huang-Yang quantum and thermal corrections

TL;DR

This paper studies how disorder, quantum, and thermal effects influence Anderson localization of quasiparticles in binary Bose mixtures, revealing complex interplay and phase-dependent localization behaviors.

Contribution

It provides a combined analytical and numerical analysis of localization phenomena considering Lee-Huang-Yang corrections and thermal effects in disordered Bose mixtures.

Findings

Disorder and Lee-Huang-Yang fluctuations can enhance localization in one component and cause delocalization in the other.

Thermal fluctuations induce multiple localization maxima in the density profiles.

Localization is weak in the flat-top droplet state due to excitation mode restrictions.

Abstract

We investigate analytically and numerically the Anderson localization of quasiparticles in binary Bose mixtures in the presence of the Lee-Huang-Yang quantum and thermal corrections subjected to correlated disordered potentials. We calculate the density profiles, the Bogoliubov quasiparticles modes, and the localization length in both the mixture and droplet phases. We show that for one-dimensional speckle potentials, the peculiar interplay of disorder and the Lee-Huang-Yang fluctuations may enhance localization in one component while inducing delocalization in the other. Our results reveal also that thermal fluctuations lead to the emergence of two and multiple localization maxima. In the droplet state, our findings uncover that the Anderson localization of quasiparticles is weak in the flat-top region since its excitation modes are restricted to those below the particle-emission threshold.