中国物理B ›› 2013, Vol. 22 ›› Issue (10): 100508-100508.doi: 10.1088/1674-1056/22/10/100508
Ali Yigita, Erhan Albayrakb
Ali Yigita, Erhan Albayrakb
摘要: The bimodal random crystal field (Δ) effects are investigated on the phase diagrams of spin-3/2 Ising model by using the effective-field theory with correlations based on two approximations: the general van der Waerden identity and the approximated van der Waerden identity. In our approach, the crystal field is either turned on or turned off randomly for a given probability p or q=1-p, respectively. Then the phase diagrams are constructed on the (Δ, kT/J) and (p, kT/J) planes for given p and Δ, respectively, when the coordination number is z=3. Furthermore, the effect of randomization of the crystal field is illustrated on the (Δ, kT/J) plane for p=0.5 when z=3, 4, and 6. All these are carried out for both approximations and then the results are compared to point out the differences. In addition to the lines of second-order phase transitions, the model also exhibits first-order phase transitions and the lines of which terminate at the isolated critical points for high p values.
中图分类号: (Lattice theory and statistics)