Critical behavior of the two-dimensional N-component Landau-Ginzburg Hamiltonian with cubic anisotropy

Article

关键词: ASHKIN-TELLER MODEL;    ORDER-DISORDER TRANSITIONS;    SYMANZIK BETA-FUNCTION;    2-COUPLING-CONSTANT PHI(4) THEORY;    RENORMALIZATION-GROUP FUNCTIONS;    CONTINUOUS PHASE-TRANSITIONS;    ACCURATE CRITICAL EXPONENTS;    QUANTUM-FIELD-THEORIES;    3-STATE POTTS MODEL;    LATTICE-GAS MODELS;   

DOI  :  10.1103/PhysRevB.66.184410

来源: SCIE

【 摘 要 】

We study the two-dimensional N-component Landau-Ginzburg Hamiltonian with cubic anisotropy. We compute and analyze the fixed-dimension perturbative expansion of the renormalization-group functions to four loops. The relations of these models with N-color Ashkin-Teller models, discrete cubic models, the planar model with fourth-order anisotropy, and the structural phase transition in adsorbed monolayers are discussed. Our results for N=2 (XY model with cubic anisotropy) are compatible with the existence of a line of fixed points joining the Ising and the O(2) fixed points. Along this line the exponent eta has the constant value 1/4, while the exponent nu runs in a continuous and monotonic way from 1 to infinity [from Ising to O(2)]. In the four-loop approximation, for Ngreater than or equal to3 we find a cubic fixed point in the region u,vgreater than or equal to0.

【 授权许可】

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