论文标题
$ν= 1/2 $的起源
Origin of the $ν=1/2$ fractional quantum Hall effect in wide quantum wells
论文作者
论文摘要
$ν= 1/2 $的分数量子大厅效应的性质近三十年前在宽量子井中观察到。先前的研究通过变异的蒙特卡洛法对其进行了研究，该方法的假设是，在零磁场处的局部密度近似值中获得的对称和反对称子带之间的横向波函数以及对称和反对称子带之间的差距仍然有效。该方法还忽略了Landau水平混合的效果。我们在这项工作中开发了一种三维固定相的蒙特卡洛法，该方法在一个有限宽度量子井中以单个框架为单个框架，在一个有限的宽度量子中，包括Landau级别混合，直接在大磁场中。该方法可以应用于一个组分状态，以及在对称和反对称带几乎退化的极限下的两个组分状态。我们的三维固定相扩散蒙特卡洛计算表明，在广泛的量子井中观察到的1/2个量子霍尔状态可能是支持非亚伯利亚激发的单位量子PFAFFIAN国家。我们希望这将激发该状态的进一步实验研究。
The nature of the fractional quantum Hall effect at $ν=1/2$ observed in wide quantum wells almost three decades ago is still under debate. Previous studies have investigated it by the variational Monte Carlo method, which makes the assumption that the transverse wave function and the gap between the symmetric and antisymmetric subbands obtained in a local density approximation at zero magnetic field remain valid even at high perpendicular magnetic fields; this method also ignores the effect of Landau level mixing. We develop in this work a three-dimensional fixed phase Monte Carlo method, which gives, in a single framework, the total energies of various candidate states in a finite width quantum well, including Landau level mixing, directly in a large magnetic field. This method can be applied to one-component states, as well two-component states in the limit where the symmetric and antisymmetric bands are nearly degenerate. Our three-dimensional fixed-phase diffusion Monte Carlo calculations suggest that the observed 1/2 fractional quantum Hall state in wide quantum wells is likely to be the one-component Pfaffian state supporting non-Abelian excitations. We hope that this will motivate further experimental studies of this state.
