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Partial entropy in finite-temperature phase transitions

Junpeng Cao·Xiaoling Cui·Zhang Qi·Wengang Lu·Qian Niu·Yupeng Wang
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Abstract

It is shown that the von Neumann entropy, a measure of quantum entanglement, does have its classical counterpart in thermodynamic systems, which we call partial entropy. Close to the critical temperature the partial entropy shows perfect finite-size scaling behavior even for quite small system sizes. This provides a powerful tool to quantify finite-temperature phase transitions as demonstrated on the classical Ising model on a square lattice and the ferromagnetic Heisenberg model on a cubic lattice.

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Junpeng Cao, Xiaoling Cui, Zhang Qi, Wengang Lu, Qian Niu, Yupeng Wang. 2007-11-28. Partial entropy in finite-temperature phase transitions. https://doi.org/10.1103/physrevb.75.172401

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