Thermodynamic properties of the spatially anisotropic triangular antiferromagnet

HAMAD, I. J.; MANUEL, LO; ADOLFO EMILIO TRUMPER

Buenos Aires

Workshop; At the frontier of the condensed matter II; 2004

Centro Atomico Constituyentes (CNEA)

We study finite temperature properties of the spatially anisotropic Heisenberg antiferromagnet on a triangular lattice. In order to fullfil Mermin Wagner´s theorem we impose a zero magnetization condition in the spin wave theory. We compute the specific heat,  the static structure factor, and the uniform static susceptibility as a function of both frustration and temperature. Motivated by experimental studies of NMR on organic superconductors, we calculate the relaxation time 1/T_1 and analyze the interplay between pressure and magnetic frustration. We also discuss the validity of a localized spin model to describe the magnetic phase of the kappa pattern of the organic superconductors.