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arXiv · 2006.03569

Transport in the non-ergodic extended phase of interacting quasiperiodic systems

Soumi Ghosh·Jyotsna Gidugu·Subroto Mukerjee
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Abstract

We study the transport properties and the spectral statistics of a one-dimensional closed quantum system of interacting spinless fermions in a quasiperiodic potential which produces a single particle mobility edge in the absence of interaction. For such systems, it has been shown that the many body eigenstates can be of three different kinds: extended and ETH (eigenstate thermalization hypothesis) obeying (thermal), localized and ETH violating (many body localized) and extended and ETH violating (non-ergodic extended). Here we investigate the non-ergodic extended phase from the point of view of level spacing statistics and charge transport. We calculate the dc conductivity and the low frequency conductivity $σ(ω)$ and show that both are consistent with sub-diffusive transport. This is contrasted with diffusive transport in the thermal phase and blocked transport in the MBL phase.

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Soumi Ghosh, Jyotsna Gidugu, Subroto Mukerjee. 2020-06-05. Transport in the non-ergodic extended phase of interacting quasiperiodic systems. https://doi.org/10.1103/physrevb.102.224203

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