Phase transition in magnetic ultra-thin films

Phạm Hương Thảo, Ngô Thị Thuận, Phan Thị Hàn Ny



In this paper, we study influence of surface anisotropy on the phase transition in antiferromagnetic and ferromagnetic ultra-thin films by using functional integral method. Besides, spin fluctuations are also given to illustrate for these phase transitions. We find that the phase transition temperature of the ultra-thin films may be higher or lower than the phase transition temperature of the corresponding bulk systems, which depends on the surface anisotropy. Moreover, we also determine crossover points at which the phase transition temperature is not influenced by the thickness of the thin film.


thin film, surface anisotropy, spin fluctuation, phase transition, functional integral method


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