General Localization Lengths for Two Interacting Particles in a Disordered Chain

TL;DR

This paper introduces a new decimation algorithm to compute localization lengths for two interacting particles in a disordered chain, revealing that interactions mainly delocalize the pair's center-of-mass motion and clarifying previous numerical discrepancies.

Contribution

A novel decimation algorithm for calculating localization lengths, offering a comprehensive understanding of two-particle propagation and interaction effects in disordered systems.

Findings

Interaction primarily delocalizes the center-of-mass motion

New algorithm provides more detailed localization length measurements

Clarifies discrepancies in previous numerical studies

Abstract

The propagation of an interacting particle pair in a disordered chain is characterized by a set of localization lengths which we define. The localization lengths are computed by a new decimation algorithm and provide a more comprehensive picture of the two-particle propagation. We find that the interaction delocalizes predominantly the center-of-mass motion of the pair and use our approach to propose a consistent interpretation of the discrepancies between previous numerical results.