Correlated Electron Research Group (CERG), RIKEN Advanced Science Institute, Wako 351-0198, Japan.
Phys Rev Lett. 2012 May 4;108(18):186803. doi: 10.1103/PhysRevLett.108.186803. Epub 2012 May 1.
The sequence of prominent fractional quantum Hall states up to ν=5/11 around ν=1/2 in a high-mobility two-dimensional electron system confined at oxide heterointerface (ZnO) is analyzed in terms of the composite fermion model. The temperature dependence of R(xx) oscillations around ν=1/2 yields an estimation of the composite fermion effective mass, which increases linearly with the magnetic field. This mass is of similar value to an enhanced electron effective mass, which in itself arises from strong electron interaction. The energy gaps of fractional states and the temperature dependence of R(xx) at ν=1/2 point to large residual interactions between composite fermions.
在 ZnO 异质界面限制的二维高迁移率电子系统中，分析了在ν=1/2 附近高达ν=5/11 的突出分数量子霍尔态的序列，这是基于复合费米子模型。在ν=1/2 附近 R(xx) 振荡的温度依赖性给出了复合费米子有效质量的估计，该质量随磁场线性增加。这个质量与增强的电子有效质量相似，而电子有效质量本身是由强电子相互作用引起的。分数量子态的能隙和 R(xx) 在ν=1/2 处的温度依赖性表明复合费米子之间存在很大的残余相互作用。
