Broken-symmetry ground states in ν=2 bilayer quantum Hall systems
Broken-symmetry ground states in ν=2 bilayer quantum Hall systems
复制标题
ν=2 双层量子霍尔系统中的破缺对称基态
DOI：
10.1103/physrevb.60.8817
复制
发表时间：
1999
影响因子：
3.7
通讯作者：
T. Jungwirth
中科院分区：
文献类型：
--
作者：
A. Macdonald;R. Rajaraman;T. Jungwirth
我们报告了朗道级填充因子 $\ensuremath{\nu}=2 下双层二维电子气的研究。$ 该系统表现出磁性和自发层间相位相干对称性破缺。我们提出了一个三参数 Slater 行列式变分波函数，它描述了整个偏置电位 $({\ensuremath{\Delta}}_{V})、$ 塞曼耦合 $({\ensuremath{\Delta}}_{z}),$ 和层间隧道振幅 $({\ensuremath{\Delta}}_{t})$ 强度范围内的基态。在此三维相图中，在 ${\ensuremath{\Delta}}_{z}^{2}={\ensuremath{\Delta}}_{V}^{2}+{\ensuremath{\Delta}}_{t}^{2}$ 表面附近的体积内部出现破缺对称态。我们获得了相图与 ${\ensuremath{\Delta}}_{t}=0、$ ${\ensuremath{\Delta}}_{z}=0,$ 和 ${\ensuremath{\Delta}}_{V}=0$ 平面相交的解析结果，并表明双层系统的微分电容在相边界处是奇异的。
We report on a study of a bilayer two-dimensional electron gas at Landau-level filling factor $\ensuremath{\nu}=2.$ The system exhibits both magnetic and spontaneous interlayer phase coherence broken symmetries. We propose a three-parameter Slater-determinant variational wave function which describes the ground state over the full range of bias-potential $({\ensuremath{\Delta}}_{V}),$ Zeeman coupling $({\ensuremath{\Delta}}_{z}),$ and interlayer tunneling amplitude $({\ensuremath{\Delta}}_{t})$ strengths. Broken-symmetry states occur inside a volume in this three-dimensional phase diagram near the ${\ensuremath{\Delta}}_{z}^{2}={\ensuremath{\Delta}}_{V}^{2}+{\ensuremath{\Delta}}_{t}^{2}$ surface. We have obtained analytic results for the intersections of the phase diagram with the ${\ensuremath{\Delta}}_{t}=0,$ ${\ensuremath{\Delta}}_{z}=0,$ and ${\ensuremath{\Delta}}_{V}=0$ planes and show that the differential capacitance of the bilayer system is singular at the phase boundary.