Phase transition and critical properties of spin-orbital interacting systems

Huai-Bao Tang; Dong-Meng Chen; Xiang-Fei Wei; Liang-Jian Zou

doi:10.1016/j.physleta.2007.07.030

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arXiv · 0709.4064

Phase transition and critical properties of spin-orbital interacting systems

Huai-Bao Tang·Dong-Meng Chen·Xiang-Fei Wei·Liang-Jian Zou

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Abstract

Phase transition and critical properties of Ising-like spin-orbital interacting systems in 2-dimensional triangular lattice are investigated. We first show that the ground state of the system is a composite spin-orbital ferro-ordered phase. Though Landau effective field theory predicts the second-order phase transition of the composite spin-orbital order, however, the critical exponents obtained by the renormalization group approach demonstrate that the spin-orbital order-disorder transition is far from the second-order, rather, it is more close to the first-order, implying that the widely observed first-order transition in many transition-metal oxides may be intrinsic. The unusual critical behavior near the transition point is attributed to the fractionalization of the composite order parameter.

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Huai-Bao Tang, Dong-Meng Chen, Xiang-Fei Wei, Liang-Jian Zou. 2007-09-26. Phase transition and critical properties of spin-orbital interacting systems. https://doi.org/10.1016/j.physleta.2007.07.030

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