FAR-INFRARED EMISSION FROM MAGNETICALLY QUANTIZED 2-DIMENSIONAL ELECTRON GASES IN GAAS ALXGA1-XAS HETEROJUNCTIONS

An investigation has been made of the far-infrared cyclotron emission from electrically heated, magnetically quantized two-dimensional elect ron gases using a technique employing a broad-band detector. Spectral resolution is obtained by using the substrate as a Fabry-Perot etalon. The experiments indicate that the system is well adapted for measurin g the electron temperature as a function of magnetic field. Further sp ectroscopic information is obtained by including a low-pass filter. Th e system has been used to investigate the emission spectrum and its in tensity in fields up to 3 T and currents up to 1 mA (current density o f 5 mA/mm). The measurements demonstrate that 20-30% of the emission o ccurs at frequencies less than omega(c).