A Spin-Freezing Phenomenonin Triangular Lattice Heisenberg Antiferromagnet CsVCl₃

Abstract

The magnetic properties of triangular lattice S=3/2 Heisenberg antiferromagnet CsVCl₃ were studied by DC magnetic susceptibility and ESR measurements using reliable pure samples free from Curie-like paramagnetic contributions at low temperatures. At T_N=14.0± 0.2, K, susceptibility exhibited the second-order transition which corresponds to a three-dimensional order with triangular spin arrangement. A spin-freezing phenomenon similar to that of spin glasses was observed below T_f=7.5, K. This behavior suggests that the ground state is not a simple 120° Néel state.