By modifying the interchange interactions and the transverse fields on the epitaxy surface layer, this paper studies the phase transition properties of an n-layer ferroelectric thin film by the Fermi-type Green＇s fun...By modifying the interchange interactions and the transverse fields on the epitaxy surface layer, this paper studies the phase transition properties of an n-layer ferroelectric thin film by the Fermi-type Green＇s function technique based on the transverse Ising model with a four-spin interaction. The special attention is given to the effect of the epitaxy surface layer on the first-order phase transition properties in the parameter space constructed by the ratios of the bulk transverse field and the bulk four-spin interaction to the bulk two-spin interaction with the framework of the higher-order decoupling approximation to the Fermi-type Green＇s function. The results show that the first-order phase transition properties will be changed significantly due to the modification of interchange interaction and transverse field parameters on the epitaxy surface layer. The dependence of the first-order phase transition properties on the thickness of ferroelectric thin films is also discussed.展开更多
基金Project supported partly by the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(Grant No. 60721001)
文摘By modifying the interchange interactions and the transverse fields on the epitaxy surface layer, this paper studies the phase transition properties of an n-layer ferroelectric thin film by the Fermi-type Green＇s function technique based on the transverse Ising model with a four-spin interaction. The special attention is given to the effect of the epitaxy surface layer on the first-order phase transition properties in the parameter space constructed by the ratios of the bulk transverse field and the bulk four-spin interaction to the bulk two-spin interaction with the framework of the higher-order decoupling approximation to the Fermi-type Green＇s function. The results show that the first-order phase transition properties will be changed significantly due to the modification of interchange interaction and transverse field parameters on the epitaxy surface layer. The dependence of the first-order phase transition properties on the thickness of ferroelectric thin films is also discussed.
