Absence of phase transitions in a class of integer spin systems
نویسندگان
چکیده
Abstract We exhibit a class of integer spin systems whose free energy can be written in term of an absolutely convergent series at any temperature. This class includes spin systems on Z interacting through infinite range pair potential polynomially decaying at large distances r at a rate 1/r with ε > 0. It also contains the Blume-Emery-Griffiths model in the disordered phase at large values of the crystal field.
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