Induced Delocalization by Correlation and Interaction in the one-dimensional Anderson Model

TL;DR

This paper investigates how long-range correlated disorder and dipole-dipole interactions induce delocalization in the one-dimensional Anderson model, using numerical exact diagonalization and proposing a new multi-particle localization definition.

Contribution

It extends the understanding of delocalization mechanisms by analyzing correlated disorder and interactions, and introduces a novel multi-particle localization measure.

Findings

Delocalized states emerge with increasing correlations.

Localization sensitivity depends on interaction range, not sign.

Proposes a new multi-particle localization definition.

Abstract

We consider long-range correlated disorder and mutual interacting particles according to a dipole-dipole coupling as modifications to the one-dimensional Anderson model. Technically we rely on the (numerical) exact diagonalization of the system's Hamilitonian. From the perspective of different localization measures we confirm and extend the picture of the emergence of delocalized states with increasing correlations. Beside these studies a definition for multi-particle localization is proposed. In the case of two interacting bosons we observe a sensitivity of localization with respect to the range of the particle-particle interaction and insensitivity to the coupling's sign, which should stimulate new theoretical approaches and experimental investigations with e.g. dipolar cold quantum gases. This revised manuscript is much more explicit compared to the initial version of the paper. Major extensions have been applied to Sects. II and III where we updated and added figures and we more extensively compared our results to the literature. Furthermore, Sect. III additionally contains a phenomenological line of reasoning that bridges from delocalization by correlation to delocalization by interaction on the basis of the multi-particle Hamilton matrix.