arXiv:1112.3847 · Europhysics Letters (EPL)

Correlated metallic two-particle bound states in quasiperiodic chains

Sergej Flach A, Mikhail Ivanchenko, Рамаз Хомерики

Published Jun 1, 2012• 31 citations

Abstract

Single-particle states in a chain with quasiperiodic potential show a metal-insulator transition upon the change of the potential strength. We consider two particles with local interaction in the single-particle insulating regime. The two-particle states change from being localized to delocalized upon an increase of the interaction strength to a nonperturbative finite value. At even larger interaction strength the states become localized again. This transition of two-particle bound states into correlated metallic ones is due to a resonant mixing of the noninteracting two-particle eigenstates. In the discovered correlated metal states two particles move coherently together through the whole chain.

DOI: 10.1209/0295-5075/98/66002

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