We consider the Ginzburg-Landau MN model that describes M N-vector cubic models with O(M)-symmetric couplings. We compute the renormalization-group functions to six-loop order in d=3. We focus on the limit N->O which describes the critical behavior of an M-vector model in the presence of weak quenched disorder. We perform for the critical exponents: y=1.330(17), v=0.678(10), eta = 0.030(3), alpha = -0.034(30), Beta = 0.349(5), omega = 0.25(10). For M greater than or equal to 2 we show that the O(M) fixed point is stable, in agreement with general nonperturbative arguments, and that no random fixed point exists.
Randomly dilute spin models: A six-loop field-theoretic study / Pelissetto, Andrea; Ettore, Vicari. - In: PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS. - ISSN 1098-0121. - STAMPA. - 62:10(2000), pp. 6393-6409. [10.1103/physrevb.62.6393]
Randomly dilute spin models: A six-loop field-theoretic study
PELISSETTO, Andrea;
2000
Abstract
We consider the Ginzburg-Landau MN model that describes M N-vector cubic models with O(M)-symmetric couplings. We compute the renormalization-group functions to six-loop order in d=3. We focus on the limit N->O which describes the critical behavior of an M-vector model in the presence of weak quenched disorder. We perform for the critical exponents: y=1.330(17), v=0.678(10), eta = 0.030(3), alpha = -0.034(30), Beta = 0.349(5), omega = 0.25(10). For M greater than or equal to 2 we show that the O(M) fixed point is stable, in agreement with general nonperturbative arguments, and that no random fixed point exists.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
