论文标题
均匀分数分数量子霍尔在填充因子ν= 3/4处
Even-Denominator Fractional Quantum Hall State at Filling Factor ν = 3/4
论文作者
论文摘要
当电子 - 电子相互作用占主导地位时，分数量子霍尔状态（FQHSS）例证了低二维二维（2D）电子系统的外来阶段。在FQHS中，特别吸引人的是在偶数级别的Landau级填充因子上观察到的，因为通常认为它们的准粒子可以遵守非亚洲统计数据，并且在拓扑量子计算中可能使用。然而，这种状态非常罕见和脆弱，通常在障碍量最低的2D电子系统的激发兰道水平上观察到。在这里，我们报告了在GAAS 2D孔系统中填充因子ν= 3/4的新的且意外的偶数级数FQH的观察，其质量异常高（迁移率）。我们的磁铁运输测量值显示，ν= 3/4的纵向电阻的最小值很大，并伴随着以（H/E2）/（3/4）为中心的发育中的高原。这种均匀的vQHS非常不寻常，因为它在最低的Landau级别和2D孔系统中观察到。虽然其起源尚不清楚，但它可能是一个非亚洲状态，这是由于复合材料费米子之间的残留相互作用而出现的。
Fractional quantum Hall states (FQHSs) exemplify exotic phases of low-disorder two-dimensional (2D) electron systems when electron-electron interaction dominates over the thermal and kinetic energies. Particularly intriguing among the FQHSs are those observed at even-denominator Landau level filling factors, as their quasi-particles are generally believed to obey non-Abelian statistics and be of potential use in topological quantum computing. Such states, however, are very rare and fragile, and are typically observed in the excited Landau level of 2D electron systems with the lowest amount of disorder. Here we report the observation of a new and unexpected even-denominator FQHS at filling factor ν = 3/4 in a GaAs 2D hole system with an exceptionally high quality (mobility). Our magneto-transport measurements reveal a strong minimum in the longitudinal resistance at ν = 3/4, accompanied by a developing Hall plateau centered at (h/e2)/(3/4). This even-denominator FQHS is very unusual as it is observed in the lowest Landau level and in a 2D hole system. While its origin is unclear, it is likely a non-Abelian state, emerging from the residual interaction between composite fermions.
