Diffusive high-temperature transport in the one-dimensional Hubbard   model
  We consider charge and spin transport in the one-dimensional Hubbard model at infinite temperature, half-filling and zero magnetization. Implementing matrix-product-operator simulations of the non-equilibrium steady states of boundary-driven open Hubbard chains for up to 100 sites we find clear evidence of diffusive transport for any (non-zero and finite) value of the interaction U. 
Tomaz Prosen and Marko Znidaric
cond-mat.str-el quant-ph