Two-loop Functional Renormalization Group of the Random Field and Random Anisotropy O(N) Models
نویسندگان
چکیده
منابع مشابه
Comment on "random-field spin models beyond 1 loop: a mechanism for decreasing the lower critical dimension".
The functional renormalization group for the random-field and random-anisotropy O(N) sigma models is studied to 2 loop. The ferromagnetic-disordered (F-D) transition fixed point is found to next order in d = 4 + epsilon for N > N(c) (N(c) = 2.834 740 8 for random field, N(c) = 9.441 21 for random anisotropy). For N < N(c) the lower critical dimension d = d(lc) plunges below d(lc) = 4: we find t...
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