Department of Physics, Princeton University, Princeton, New Jersey 08544, USA.
Phys Rev Lett. 2012 Dec 28;109(26):266806. doi: 10.1103/PhysRevLett.109.266806. Epub 2012 Dec 27.
We study the nature of the ν=5/2 quantum Hall state in wide quantum wells under the mixing of electronic subbands and Landau levels. A general method is introduced to analyze the Moore-Read pfaffian state and its particle-hole conjugate, the anti-pfaffian state, under periodic boundary conditions in a "quartered" Brillouin zone scheme containing both even and odd numbers of electrons. By examining the rotational quantum numbers on the torus, we show spontaneous breaking of the particle-hole symmetry can be observed in finite-size systems. In the presence of electronic-subband and Landau-level mixing, the particle-hole symmetry is broken in such a way that the anti-pfaffian state is unambiguously favored, and becomes more robust in the vicinity of a transition to the compressible phase, in agreement with recent experiments.
我们研究了在宽量子阱中电子子带和 Landau 能级混合情况下ν=5/2 量子 Hall 态的性质。介绍了一种通用方法来分析在“四分一”布里渊区方案下具有偶数和奇数电子的周期性边界条件下的 Moore-Read pfaffian 态及其粒子-空穴共轭 anti-pfaffian 态。通过在环面上检查转动量子数，我们表明在有限尺寸系统中可以观察到自发破缺的粒子-空穴对称性。在存在电子子带和 Landau 能级混合的情况下，粒子-空穴对称性以这样的方式被打破，即 anti-pfaffian 态被明确地偏爱，并且在接近可压缩相的转变附近变得更加稳健，这与最近的实验结果一致。
