Conjectures on exact solution of three - dimensional (3D) simple orthorhombic Ising lattices
Shenyang National Laboratory for Materials Science, Institute of Metal Research and International Centre for Materials Physics, Chinese Academy of Sciences（中国科学院金属研究所、国际材料物理中心和沈阳材料科学国家研究中心）
We report the conjectures on the three-dimensional (3D) Ising model on simple orthorhombic lattices, together with the details of calculations for a putative exact solution. Two conjectures, an additional rotation in the fourth curled-up dimension and the weight factors on the eigenvectors, are proposed to serve as a boundary condition to deal with the topologic problem of the 3D Ising model. The partition function of the 3D simple orthorhombic Ising model is evaluated by spinor analysis, by employing these conjectures. Based on the validity of the conjectures, the critical temperature of the simple orthorhombic Ising lattices could be determined by the relation of KK* = KK' + KK'' + K'K'' or sinh 2K sinh 2(K' + K'' + K'K''/K) = 1. For a simple cubic Ising lattice, the critical point is putatively determined to locate exactly at the golden ratio xc = exp(-2Kc) = (sq(5) - 1)/2, as derived from K* = 3K or sinh 2K sinh 6K = 1. If the conjectures would be true, the specific heat of the simple orthorhombic Ising system would show a logarithmic singularity at the critical point of the phase transition. The spontaneous magnetization and the spin correlation functions of the simple orthorhombic Ising ferromagnet are derived explicitly. The putative critical exponents derived explicitly for the simple orthorhombic Ising lattices are alpha = 0, beta = 3/8, gamma = 5/4, delta = 13/3, eta = 1/8 and nu = 2/3, showing the universality behavior and satisfying the scaling laws. The cooperative phenomena near the critical point are studied and the results obtained based on the conjectures are compared with those of the approximation methods and the experimental findings. The 3D to 2D crossover phenomenon differs with the 2D to 1D crossover phenomenon and there is a gradual crossover of the exponents from the 3D values to the 2D ones.
Phase transitions of the mixed spin-1/2 and spin-S Ising model on a three-dimensional decorated lattice with a layered structure
在一个精确映射到简单自旋1/2伊辛模型的框架下，研究了具有层状磁结构的三维缀饰晶格上自旋1/2和自旋S（S >= 1/2）混合伊辛模型的相变.对于混合自旋的分层伊辛模型，这种映射对应产生了合理的结果，或者通过采用正交晶格上自旋为1/2的伊辛模型的简化解[Z. D. Zhang，Philos.Mag.87（2007）5309-5419]或通过对四重晶格上的相应自旋1/2伊辛模型进行广泛的蒙特卡罗模拟。结果表明，临界行为显着依赖于轴向零场分裂参数，层间和层内相互作用的相对强度。引人注目的自发秩序捕获的“准1D”自旋系统中发现的相互作用参数的限制区域中，零场分裂参数的力量，所有整数值的装饰自旋对他们的“非磁性”的自旋状态。
Response to arXiv:0811.1802 "Comment on 'Conjectures on exact solution of three-dimensional (3D) Ising lattices'" by Perk and Singularities at/near infinite temperature: Reply to Perk's Rejoinder arXiv:0901.2935
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Okinawa Institute of Science and Technology（冲绳科学技术大学院大学）
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