Yi Hangmo
Department of Physics, Soongsil University, Seoul 156-743, Korea and Institute for Integrative Basic Sciences, Soongsil University, Seoul 156-743, Korea.
Phys Rev E Stat Nonlin Soft Matter Phys. 2015 Jan;91(1):012146. doi: 10.1103/PhysRevE.91.012146. Epub 2015 Jan 28.
I investigate the quantum phase transition of the transverse-field quantum Ising model in which nearest neighbors are defined according to the connectivity of scale-free networks. Using a continuous-time quantum Monte Carlo simulation method and the finite-size scaling analysis, I identify the quantum critical point and study its scaling characteristics. For the degree exponent λ=6, I obtain results that are consistent with the mean-field theory. For λ=4.5 and 4, however, the results suggest that the quantum critical point belongs to a non-mean-field universality class. Further simulations indicate that the quantum critical point remains mean-field-like if λ>5, but it continuously deviates from the mean-field theory as λ becomes smaller.
我研究了横向场量子伊辛模型的量子相变，其中最近邻是根据无标度网络的连通性定义的。使用连续时间量子蒙特卡罗模拟方法和有限尺寸标度分析，我确定了量子临界点并研究了其标度特性。对于度指数λ = 6，我得到了与平均场理论一致的结果。然而，对于λ = 4.5和4，结果表明量子临界点属于非平均场普适类。进一步的模拟表明，如果λ>5，量子临界点仍然类似平均场，但随着λ变小，它会不断偏离平均场理论。
