A quantum critical trio: solvable models of finite temperature crossovers near quantum phase transitions
نویسنده
چکیده
The physics of three simple solvable quantum models is reviewed in some detail: the spin 1/2 XX chain (and the related dilute spinless Fermi gas), the Ising chain in a transverse field, and the large N limit of the O(N) quantum rotor model. A unified scaling description is presented, and the many common features among the models are highlighted. The crossovers in these systems are the simplest paradigms of finite temperature physics near quantum critical points. Typeset using REVTEX
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