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Critical thermodynamics of three-dimensional MN-component field model with cubic anisotropy from higher-loop εexpansion

Andrei Mudrov·Konstantin Varnashev
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Abstract

The critical thermodynamics of an $MN$-component field model with cubic anisotropy relevant to the phase transitions in certain crystals with complicated ordering is studied within the four-loop $\ve$ expansion using the minimal subtraction scheme. Investigation of the global structure of RG flows for the physically significant cases M=2, N=2 and M=2, N=3 shows that the model has an anisotropic stable fixed point with new critical exponents. The critical dimensionality of the order parameter is proved to be equal to $N_c^C=1.445(20)$, that is exactly half its counterpart in the real hypercubic model.

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Andrei Mudrov, Konstantin Varnashev. 2001-08-19. Critical thermodynamics of three-dimensional MN-component field model with cubic anisotropy from higher-loop εexpansion. https://doi.org/10.1088/0305-4470%2F34%2F23%2F102

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