J.V. Harzer, B. Hillebrands, et al.
Journal of Magnetism and Magnetic Materials
The XXZ spin Hamiltonian H = - Σ(I, j) (SxiSxj + SyiSyj + ⋋SziSzj) is simulated for quantum spins. The XY model (⋋ = 0) has a Kosterlitz- Thouless phase transition at TKT = 0.45 + 0.05, slightly above which the specific heat has a finite peak. The vortex density has a non-zero value in the low-temperature limit, probably due to quantum fluctuations. The critical temperature holds up at least to ⋋= -0.8. The Ising transition temperature TIsing is measured for Ising-like antiferromagnets ⋋ < - 1 and is found to drop off to zero in a manner consistent with the reciprocal-logarithmic behavior Tc α - 1/log/-⋋1/as proposed for the classical model. © 1985 IOP Publishing Ltd.
J.V. Harzer, B. Hillebrands, et al.
Journal of Magnetism and Magnetic Materials
A. Ney, R. Rajaram, et al.
Journal of Magnetism and Magnetic Materials
Heinz Schmid, Hans Biebuyck, et al.
Journal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures
Corneliu Constantinescu
SPIE Optical Engineering + Applications 2009