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arXiv · 1811.01912

Many-body localization in a quasiperiodic Fibonacci chain

Abstract

We study the many-body localization (MBL) properties of a chain of interacting fermions subject to a quasiperiodic potential such that the non-interacting chain is always delocalized and displays multifractality. Contrary to naive expectations, adding interactions in this systems does not enhance delocalization, and a MBL transition is observed. Due to the local properties of the quasiperiodic potential, the MBL phase presents specific features, such as additional peaks in the density distribution. We furthermore investigate the fate of multifractality in the ergodic phase for low potential values. Our analysis is based on exact numerical studies of eigenstates and dynamical properties after a quench.

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Nicolas Macé, Nicolas Laflorencie, Fabien Alet. 2018-11-05. Many-body localization in a quasiperiodic Fibonacci chain. https://doi.org/10.21468/scipostphys.6.4.050

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