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arXiv · 1103.3431

On the structure of typical states of a disordered Richardson model and many-body localization

Francesco Buccheri·Andrea De Luca·Antonello Scardicchio
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Abstract

We present a thorough numerical study of the Richardson model with quenched disorder (a fully-connected XX-model with longitudinal random fields). We study the onset of delocalization in typical states (many-body delocalization) and the delocalized phase which extends over the whole range of coupling strength in the thermodynamic limit. We find a relation between the inverse participation ratio, the Edwards-Anderson order parameter and the average Hamming distance between spin configurations covered by a typical eigenstate for which we conjecture a remarkably simple form for the thermodynamic limit. We also studied the random process defined by the spread of a typical eigenstate on configuration space, highlighting several similarities with hopping on percolated hypercube, a process used to mimic the slow relaxation of spin glasses.

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Francesco Buccheri, Andrea De Luca, Antonello Scardicchio. 2011-06-10. On the structure of typical states of a disordered Richardson model and many-body localization. https://doi.org/10.1103/physrevb.84.094203

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