Schliemann J, MacDonald AH
Physikalisches Institut, Universitat Bayreuth, D-95440 Bayreuth, Germany.
Phys Rev Lett. 2000 May 8;84(19):4437-40. doi: 10.1103/PhysRevLett.84.4437.
We present an exact diagonalization study of bilayer quantum Hall systems at filling factor nu = 2 in the spherical geometry. We find the high-Zeeman-coupling phase boundary of the broken symmetry canted antiferromagnet is given exactly by previous Hartree-Fock mean-field theories, but that the state's stability at weak Zeeman coupling has been qualitatively overestimated. In the absence of interlayer tunneling, degeneracies occur between total spin multiplets due to the Hamiltonian's invariance under independent spin rotations in top and bottom two-dimensional electron layers.
我们展示了在球形几何结构中填充因子为ν = 2的双层量子霍尔系统的精确对角化研究。我们发现，先前的哈特里 - 福克平均场理论准确给出了破缺对称性倾斜反铁磁体的高塞曼耦合相边界，但该状态在弱塞曼耦合下的稳定性被定性地高估了。在没有层间隧穿的情况下，由于哈密顿量在顶部和底部二维电子层中独立自旋旋转下的不变性，总自旋多重态之间会出现简并。
