Žukovič Milan, Kalagov Georgii
Department of Theoretical Physics and Astrophysics, Institute of Physics, Faculty of Science, P. J. Šafárik University in Košice, Park Angelinum 9, 041 54 Košice, Slovakia.
Phys Rev E. 2022 Mar;105(3-1):034129. doi: 10.1103/PhysRevE.105.034129.
We study effects of competing pairwise higher-order interactions (HOI) with alternating signs and exponentially decreasing intensity on critical behavior of the XY model. It is found that critical properties of such a generalized model can be very different from the standard XY model and can strongly depend on whether the number of HOI terms is odd or even. Inclusion of any odd number of HOI terms results in two consecutive phase transitions to distinct ferromagnetic quasi-long-range order phases. Even number of HOI terms leads to two phase transitions only if the decay of the HOI intensities is relatively slow. Then the high-temperature transition to the ferromagnetic phase is followed by another transition to a peculiar competition-induced canted ferromagnetic phase. In the limit of an infinite number of HOI terms only one phase transition is confirmed, and under the conditions of fierce competition between the even and odd terms the transition temperature can be suppressed practically to zero.
我们研究了具有交替符号和指数衰减强度的竞争成对高阶相互作用（HOI）对XY模型临界行为的影响。结果发现，这种广义模型的临界性质可能与标准XY模型有很大不同，并且可能强烈依赖于HOI项的数量是奇数还是偶数。包含任何奇数个HOI项会导致连续两次相变，进入不同的铁磁准长程有序相。只有当HOI强度的衰减相对较慢时，偶数个HOI项才会导致两次相变。然后，从高温到铁磁相的转变之后是另一个转变，进入一个特殊的竞争诱导倾斜铁磁相。在HOI项数量无限的极限情况下，只确认了一次相变，并且在偶数项和奇数项之间激烈竞争的条件下，转变温度实际上可以被抑制到零。
