文献类型：期刊文献

英文题名：Special transitions in an O(n) loop model with an Ising-like constraint

作者：Fu, Zhe[1];Guo, Wenan[2];Blote, Henk W. J.[2,3]

第一作者：付喆

通讯作者：Guo, WA[1]

机构：[1]Xinxiang Univ, Coll Phys & Elect Engn, Xinxiang 453003, Peoples R China;[2]Beijing Normal Univ, Dept Phys, Beijing 100875, Peoples R China;[3]Leiden Univ, Inst Lorentz, POB 9506, NL-2300 RA Leiden, Netherlands

第一机构：新乡学院物理与电子工程学院

通讯机构：[1]corresponding author), Beijing Normal Univ, Dept Phys, Beijing 100875, Peoples R China.

年份：2016

卷号：93

期号：4

外文期刊名：PHYSICAL REVIEW E

收录：;EI(收录号：20161602267586);Scopus(收录号：2-s2.0-84963579578);WOS:【SCI-EXPANDED(收录号:WOS:000373586200003)】；

基金：We thank Eric Vernier for informing us about the appearance of Ref. [14]. We are also indebted to Bernard Nienhuis for sharing his valuable insights. H.B. is grateful for the hospitality extended to him by the Beijing Normal University Faculty of Physics, where this work was performed. This research was supported by National Natural Science Foundation of China Grants No. 11175018 and No. 11447154 and by the Fundamental Research Funds for the Central Universities (China).

语种：英文

外文关键词：Topology - Transfer matrix method

摘要：We investigate the O(n) nonintersecting loop model on the square lattice under the constraint that the loops consist of 90-deg bends only. The model is governed by the loop weight n, a weight x for each vertex of the lattice visited once by a loop, and a weight z for each vertex visited twice by a loop. We explore the (x,z) phase diagram for some values of n. For 0 < n < 1, the diagram has the same topology as the generic O(n) phase diagram with n < 2, with a first-order line when z starts to dominate and an O(n)-like transition when x starts to dominate. Both lines meet in an exactly solved higher critical point. For n > 1, the O(n)-like transition line appears to be absent. Thus, for z = 0, the (n,x) phase diagram displays a line of phase transitions for n <= 1. The line ends at n = 1 in an infinite-order transition. We determine the conformal anomaly and the critical exponents along this line. These results agree accurately with a recent proposal for the universal classification of this type of model, at least in most of the range -1 <= n <= 1. We also determine the exponent describing crossover to the generic O(n) universality class, by introducing topological defects associated with the introduction of "straight" vertices violating the 90-deg-bend rule. These results are obtained by means of transfer-matrix calculations and finite-size scaling.