Abstract
The photoluminescence (PL) spectrum of modulation-doped GaAs/AlGaAs quantum wells and heterojunctions (HJ) is studied under a magnetic field (B) applied parallel to the two-dimensional electron gas (2DEG) layer. The effect of B ∥ strongly depends on the electron-hole separation, and we revealed remarkable B ∥-induced modifications of the PL spectra in both types of heterostructures. A model considering the direct optical transitions between the conduction and valence subbands that are shifted in k-space under B ∥, accounts qualitatively for the observed spectral modifications. In the HJs, the 2DEG-hole PL intensity is strongly enhanced relatively to the bulk exciton PL with increasing B ∥. This means that the distance between the photoholes and the 2DEG decreases with increasing B ∥, and thus free holes are responsible for the 2DEG-hole PL.
Original language | English (US) |
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Article number | 045303 |
Journal | Physical Review B - Condensed Matter and Materials Physics |
Volume | 71 |
Issue number | 4 |
DOIs | |
State | Published - Jan 2005 |
Externally published | Yes |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics