Specific Heat of discrete systems and high - temperature series : new interpolation scheme and examples on spin - 1 / 2 Heisenberg models
نویسندگان
چکیده
We present a model for evaluating the specific heat of lattice spin systems. It is based on the knowledge of high-temperature series expansions, the total entropy of the system and the low-temperature expected behavior of the specific heat as well as the ground-state energy. By the choice of an appropriate variable (entropy as a function of energy), a stable interpolation scheme between low and high temperature is performed. Contrary to previous methods, the constrain that the total entropy is log(2S + 1) for a spin S on each site is automatically satisfied. We present some applications to Heisenberg models on two-and three-dimensional lattices.
منابع مشابه
Specific heat and high-temperature series of lattice models: Interpolation scheme and examples on quantum spin systems in one and two dimensions
We have developed a method for evaluating the specific heat of lattice spin systems. It is based on the knowledge of high-temperature series expansions, the total entropy of the system, and the low-temperature expected behavior of the specific heat as well as the ground-state energy. By the choice of an appropriate variable ~entropy as a function of energy!, a stable interpolation scheme betwee...
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