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arXiv · 1712.06892

Many-body localization in the Fock space of natural orbitals

Wouter Buijsman·Vladimir Gritsev·Vadim Cheianov
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Abstract

We study the eigenstates of a paradigmatic model of many-body localization in the Fock basis constructed out of the natural orbitals. By numerically studying the participation ratio, we identify a sharp crossover between different phases at a disorder strength close to the disorder strength at which subdiffusive behaviour sets in, significantly below the many-body localization transition. We repeat the analysis in the conventionally used computational basis, and show that many-body localized eigenstates are much stronger localized in the Fock basis constructed out of the natural orbitals than in the computational basis.

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Wouter Buijsman, Vladimir Gritsev, Vadim Cheianov. 2017-12-19. Many-body localization in the Fock space of natural orbitals. https://doi.org/10.21468/scipostphys.4.6.038

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