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arXiv · 1301.1586

Effect of biquadratic exchange on phase transitions of a planar classical Heisenberg ferromagnet

M. Žukovič·T. Idogaki·K. Takeda
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Abstract

Effect of biquadratic exchange on phase transitions of a planar classical Heisenberg (or XY) ferromagnet on a stacked triangular lattice is investigated by Standard Monte Carlo and Histogram Monte Carlo simulations in the region of a bilinear to biquadratic exchange interaction ratio $J_{1}/J_{2} \leq 1$. The biquadratic exchange is found to cause separate second-order phase transitions in a strong biquadratic exchange limit, followed by simultaneous dipole and quadrupole ordering, which is of first order for an intermediate range of the exchange ratio and changes to a second-order one again as $J_{1}/J_{2}$ is further increased. Thus, a phase diagram featuring both triple and tricritical points is obtained. Furthermore, a finite-size scaling analysis is used to calculate the critical indices for both dipole and quadrupole kinds of ordering.

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M. Žukovič, T. Idogaki, K. Takeda. 2013-01-08. Effect of biquadratic exchange on phase transitions of a planar classical Heisenberg ferromagnet. https://doi.org/10.1016/s0921-4526(01)00396-9

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