Department of Physics, University of California, San Diego, California 92093, USA.
Phys Rev Lett. 2013 May 31;110(22):220401. doi: 10.1103/PhysRevLett.110.220401. Epub 2013 May 29.
We investigate the thermodynamic properties of a half-filled SU(2N) Hubbard model in the two-dimensional square lattice by the method of the determinant quantum Monte Carlo simulation, which is free of the fermion "sign problem." The large number of hyperfine-spin components enhances spin fluctuations, which facilitates the Pomeranchuk cooling to temperatures comparable to the superexchange energy scale in the case of SU(6). Various physical quantities including entropy, charge fluctuations, and spin correlations are calculated.
我们通过行列式量子蒙特卡罗模拟方法研究了二维正方形格子中填满一半的 SU(2N) Hubbard 模型的热力学性质，该方法不受费米子“符号问题”的影响。大量的超精细自旋分量增强了自旋涨落，这使得在 SU(6)的情况下，Pomeranchuk 冷却到与超交换能量尺度相当的温度成为可能。我们计算了各种物理量，包括熵、电荷涨落和自旋关联。
