Axial and off-axial dynamic transitions in uniaxially anisotropic Heisenberg ferromagnet: A comparison
نویسنده
چکیده
Uniaxially anisotropic Heisenberg ferromagnet, in presence of a magnetic field varying sinusoidally in time, is studied by Monte Carlo simulation. The axial (field applied only along the direction of anisotropy) and off-axial (field applied only along the direction which is perpendicular to the direction of anisotropy) dynamic transitions are studied. By studying the distribution of dynamic order parameter component it is observed that the axial transition is discontinuous for low anisotropy and becomes continuous in high anisotropy. The off-axial transition is found to be continuous for all values of anisotropy. In the infinite anisotropy limit, both types of transitions are compared with that observed in an Ising ferromagnet for the same value of the field and frequency. The infinitely anisotropic axial transition and the dynamic transition in the Ising ferromagnet occur at different temperatures whereas the infinitely anisotropic off-axial transition and the equilibrium ferro-para transition in the Ising model occur at same temperature.
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