Low-temperature large-distance asymptotics of the transversal two-point   functions of the XXZ chain
  We derive the low-temperature large-distance asymptotics of the transversal two-point functions of the XXZ chain by summing up the asymptotically dominant terms of their expansion into form factors of the quantum transfer matrix. Our asymptotic formulae are numerically efficient and match well with known results for vanishing magnetic field and for short distances and magnetic fields below the saturation field. 
Maxime Dugave, Frank G\"ohmann and Karol K. Kozlowski
cond-mat.stat-mech hep-th math-ph math.MP