摘要
We explore the Potts model on the generalized decorated square lattice,with both nearest(J1)and next-nearest(J2)neighbor interactions.Using the tensor renormalization-group method augmented by higher order singular value decompositions,we calculate the spontaneous magnetization of the Potts model with q=2,3,and 4.The results for q=2 allow us to benchmark our numerics using the exact solution.For q=3,we find a highly degenerate ground state with partial order on a single sublattice,but with vanishing entropy per site,and we obtain the phase diagram as a function of the ratio J2/J1.There is no finite-temperature transition for the q=4 case when J1=J2,whereas the magnetic susceptibility diverges as the temperature goes to zero,showing that the model is critical at T=0.
作者
秦明普
陈靖
陈巧妮
谢志远
孔鑫
赵汇海
Bruce Normand
向涛
QIN Ming-Pu;CHEN Jing;CHEN Qiao-Ni;XIE Zhi-Yuan;KONG Xin;ZHAO Hui-Hai;Bruce Normand;XIANG Tao(Institute of Physics,Chinese Academy of Sciences,Beijing 100190;Department of Chemistry,Frick Laboratory,Princeton University,Princeton,New Jersey 08544,USA;Department of Physics,Renmin University of China,Beijing 100872)
基金
Supported by the National Natural Science Foundation of China under Grant Nos 10934008,10874215 and 11174365
the National Basic Research Program of China under Grant Nos 2012CB921704 and 2011CB309703.