Thurs. seminar

[Cond.Matt. & Stat.Mech.Section]

SEMINAR on  Disorder and strong electron correlations

 

 Thursday, 7 April -  11:30 a.m.



Luigi Stasi Seminar Room,  Leonardo Building - first floor

  

Antonello SCARDICCHIO     ( I.C.T.P. )



"The typical states of a disordered Richardson model and many-body localization"



Abstract

 

We present a thorough numerical study of the Richardson model with quenched disorder (a fully-connected XX-model with longitudinal random fields).  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 find a sudden onset of an exponentially large IPR on the space of spin configurations, although local observables (single-spin expectation values) never achieve thermalization.  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.