论文标题
新的有序阶段几何沮丧的广义$ xy $型号
New ordered phase in geometrically frustrated generalized $XY$ model
论文作者
论文摘要
通过蒙特卡洛模拟研究了三角形晶格上具有抗磁磁性（AFM）和三阶抗7型（AN3）耦合的几何沮丧的$ XY $模型的临界特性。发现这样的概括导致一个相图由三个不同的准范围有序（QLRO）阶段组成。与具有二阶抗主体（AN2）耦合的模型相比，除了AFM和AN3相外，它们分别出现在相对较强的AFM和AN3相互作用的范围内，它还包括一个附加的复杂倾斜的抗铁磁（CAFM）相。由于AFM和AN3耦合之间的竞争，它在较低的温度下出现，在AFM和AN3阶段之间楔入，这在模型中与AN2耦合不存在。 AFM-CAFM和AN3-CAFM相变的结论分别属于弱的Ising和弱三态POTTS通用类别。此外，这三个QLRO阶段还具有标准和广义性手势的真实LRO，这两者都在二阶相变，具有非临界临界指数的二阶相变，并且临界温度略高于磁性和nematoric阶订单转变温度。
Critical properties of a geometrically frustrated generalized $XY$ model with antiferromagnetic (AFM) and third-order antinematic (AN3) couplings on a triangular lattice are studied by Monte Carlo simulation. It is found that such a generalization leads to a phase diagram consisting of three different quasi-long-range ordered (QLRO) phases. Compared to the model with the second-order antinematic (AN2) coupling, besides the AFM and AN3 phases which appear in the limits of relatively strong AFM and AN3 interactions, respectively, it includes an additional complex canted antiferromagnetic (CAFM) phase. It emerges at lower temperatures, wedged between the AFM and AN3 phases, as a result of the competition between the AFM and AN3 couplings, which is absent in the model with the AN2 coupling. The AFM-CAFM and AN3-CAFM phase transitions are concluded to belong to the weak Ising and weak three-state Potts universality classes, respectively. Additionally, all three QLRO phases also feature true LRO of the standard and generalized chiralities, which both vanish simultaneously at second-order phase transitions with non-Ising critical exponents and the critical temperatures slightly higher than the magnetic and nematic order-disorder transition temperatures.
