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arXiv · 2003.00698

Multifractality of correlated two-particle bound states in quasiperiodic chains

Diana Thongjaomayum·Sergej Flach·Alexei Andreanov
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Abstract

We consider the quasiperiodic Aubry-Andr\'e chain in the insulating regime with localised single-particle states. Adding local interaction leads to the emergence of extended correlated two-particle bound states. We analyse the nature of these states including their multifractality properties. We use a projected Green function method to compute numerically participation numbers of eigenstates and analyse their dependence on the energy and the system size. We then perform a scaling analysis. We observe multifractality of correlated extended two-particle bound states, which we confirm independently through exact diagonalisation.

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Diana Thongjaomayum, Sergej Flach, Alexei Andreanov. 2020-03-02. Multifractality of correlated two-particle bound states in quasiperiodic chains. https://doi.org/10.1103/physrevb.101.174201

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