Optical Spectroscopy of Quantum-Layered Semiconductors in High Magnetic Field

近年来，高质量半导体异质结构的制造导致了二维电子气体系统中新的和显著的物理发现。磁输运实验表明，当电子在朗道能级填充时具有分数值时，会发生电阻率异常。随后的理论研究表明，分数量子霍尔效应是一种新的协同多体电子流体的表现。虽然大多数实验使用电输运，但我们最近的光学研究将导致对凝聚电子状态的更好理解，并可能导致新的电子-电子相互作用。这项工作将是对GaAs量子阱中二维电子系统的光学研究，温度低至。05K和直流磁场至30特斯拉。光谱技术包括带隙发射、吸附和反射率以及非弹性光散射。新型光纤系统将用于温度和磁场极端条件下的光散射实验。

The recent fabrication of high-quality semiconductor heterostructures has led to novel and remarkable physics discovered in two-dimensional electron gas systems. Magneto- transport experiments have shown that resistivity anomalies occur when the electrons have fractional values for Landau level filling. Subsequent theoretical studies revealed that the fractional quantum Hall effect is a manifestation of a new cooperative many-body electron fluid. although most of the experiments use electrical transport, our recent optical investigations will lead to a better understanding of the condensed electron state and possibly to new electron-electron interactions. This work will be an optical study of the two- dimensional electron system in GaAs quantum wells to temperatures as low as .05K and dc magnetic fields to 30 tesla. Spectroscopic techniques involve bandgap emission, adsorption and reflectivity, and inelastic light scattering. New fiber-optic systems will be implemented for light scattering experiments at these extrema of temperature and magnetic field.