INTERBAND MAGNETO-SPECTROSCOPY OF A HIGH-DENSITY TWO-DIMENSIONAL ELECTRON GAS IN A STRONG IN-PLANE MAGNETIC FIELD

摘要

We report results of temperature and field dependent studies of interband optical absorption and photoluminescence in a two-dimensional electron gas in a strong in-plane magnetic field (up to 45 T). We observe a field dependent shift of the Fermi energy with both the magnitude and sign of the shift varying with magnetic field. Simultaneous low temperature magneto-photoluminescence measurements reveal a monotonically increasing blue shift accompanied by a quenching of the intensity. A theoretical treatment based on a single particle picture and taking into account the diamagnetic shift as well as a shift due to an anisotropic effective mass cannot qualitatively reproduce our experimental results, indicating that many-body interactions may be important.