Artículo de revista
Dynamic properties of a classical anisotropic Heisenberg chain under external magnetic field
Fecha
2005-01-31Registro en:
PHYSICA B-CONDENSED MATTER 355 (1-4): 1-8 JAN 31 2005
0921-4526
Autor
Davis, Sergio
Gutiérrez Gallardo, Gonzalo
Institución
Resumen
We investigate the dynamic properties of a classical anisotropic Heisenberg chain interacting with an external magnetic field at different temperatures. Properties such as time-dependent energy autocorrelation and space-time spin-spin correlation are obtained by solving the dynamic equation Si = Si x dels(i)H. While the static spin-spin correlation length decreases as the system is heated up, it increases when an external magnetic field is present. The time-dependent spin-spin correlation decreases when the system is heated up, resulting in a decrease of the spin-diffusion speed. The presence of the magnetic field contributes to the order, and therefore produces an increase of the spin-diffusion speed. In contrast, the single-ion type anisotropy behaves dynamically as a local field, inducing disorder in the chain.