The excitation operator method in the spin dynamics of the   one-dimensional XXZ model
  We develop the excitation operator method, which is designed to solve the Heisenberg equation of motion by constructing the excitation operators. We use it to study the spin dynamics in the one-dimensional XXZ model. We find the diffusive spin transport in the gapped phase at the high temperature limit. 
Pei Wang
cond-mat.str-el cond-mat.mes-hall math-ph math.MP