Spin States and Entropy of Ising Spin Glasses
نویسندگان
چکیده
The relative volume of spin states in the phase space is introduced for the ±J model of spin glasses. Analysis of its temperature dependence shows that the Nishimori line separates the pure ferromagnetic-like region in the high-temperature side of the ferromagnetic phase from the randomness-dominated region in the low-temperature side. The peak value of the relative volume of the perfect ferromagnetic state is shown to be equivalent to the entropy. Upper and lower bounds on the entropy are derived, which determine the value of the entropy quite precisely.
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