Spectral diffusion and scaling of many-body delocalization transitions
  We analyze the role of spectral diffusion in the problem of many-body delocalization in quantum dots and in extended systems. The spectral diffusion parametrically enhances delocalization, modifying the scaling of the delocalization threshold with the interaction coupling constant. 
I.V. Gornyi, A.D. Mirlin, D.G. Polyakov, and A.L. Burin
cond-mat.mes-hall cond-mat.dis-nn cond-mat.stat-mech