Lu, HT , Peking Univ, Sch Phys, Beijing 100871, Peoples R China
部门归属:
Peking Univ, Sch Phys, Beijing 100871, Peoples R China; Chinese Acad Sci, Inst Theoret Phys, Beijing 100080, Peoples R China; Chinese Acad Sci, Interdisciplinary Ctr Theoret Studies, Beijing 100080, Peoples R China; Beijing Normal Univ, Dept Phys, Beijing 100875, Peoples R China
英文摘要:
The temperature dependence of the specific heat and spin susceptibility of spin ladders with cyclic four-spin interactions in the rung-singlet phase is explored by making use of the transfer-matrix renormalization group method. The values of the spin gap are extracted from the specific heat and susceptibility, respectively. It is found that for different relative strengths between interchain and intrachain interactions, the spin gap is approximately linear with the cyclic four-spin interaction in the region far away from the critical point. Furthermore, we show that the dispersion for the one-triplet magnon branch can be obtained by numerically fitting the partition function.
Lu, H. T.,Sun, L. Q.,Qin, Shaojin,et al. Transfer-matrix renormalization group study of spin ladders with cyclic four-spin interactions[J]. PHYSICAL REVIEW B,2006,74(22):-.