LOW DIMENSIONAL DEVICES - HIGH MAGNETIC-FIELD AND OPTICAL SPECTROSCOPY STUDIES OF RESONANT TUNNELING AND QUANTUM-WELL PHENOMENA

Double barrier resonant tunnelling structures have been extensively investigated for their application as high frequency (up to 1 THz) microwave oscillators. In this presentation the general properties of these devices will be reviewed and the investigation of their physical characteristics by means of high magnetic fields and optical spectroscopy will be described. n-type, p-type and p-i-n variants of this type of structure will be considered. The following topics will be addressed: 1. electron and hole energy relaxation and space-charge buildup effects in the quantum well 2. electroluminescence phenomena and hot hole effects 3. the complicated ε(k∥) and negative effective mass behaviour of hole states in the quantum well.