Thermodynamic properties of two-dimensional charged spin-1/2 Fermi gases

Abstract

Based on the mean-field theory, we investigate the thermodynamic properties of the two-dimensional (2D) charged spin-1/2 Fermi gas. Landé factor g is introduced to measure the strength of the paramagnetic effect. There is a competition between diamagnetism and paramagnetism in the system. The larger is the Landé factor, the smaller are the entropy and specific heat. Diamagnetism tends to increase entropy, while paramagnetism leads to the decrease of entropy. We find there exists a critical value of Landé factor for the transition point due to the competition. The entropy of the system increases with the magnetic field when g < 0.58. With the growth of paramagnetism, when g > 0.58, the entropy first decreases with the magnetic field, then reaches a minimum value, and finally increases again. Both the entropy and specific heat increase with the temperature, and no phase transition occurs. The specific heat tends to a constant value at the high-temperature limit, and it approaches to zero at very low temperatures, which have been proved by the analytical calculation.

Structure transition in Cu crystallization

“…At some point, one of the most important characteristics of crystallization is symmetry. Crystallization changes the solid pattern of the system and destroys its symmetry [11][12][13]. Before the temperature of a liquid phase approaches the freezing point, the system has spatial symmetry.…”