Preparation and measurement of far-infrared electroluminescence emitter based on quantum confined acceptors

GaAs/AlAs triple-quantum-well samples were grown by molecular beam epitaxy, and the noddle GaAs quantum-well layer was delta-doped at the well centre with Be shallow acceptors. Then the far-infrared Teraherz prototype emitter was fabricated using the samples. Electroluminescence (EL) and current-voltage characteristics (I-V) were measured at 4.5 K In the EL spectrum, a wide peak was observed clear 222 cm(-1), which is attributed to the lie acceptor's radiative transitions from the excited odd-parity states to the ground state Nevertheless, the emission signal was weakened by non-radiative relaxation processes. In the I-V curve, the negative differential resistance characteristic at the position of 0 72 and 1. 86 V was also observed clearly. This is attributed to the resonant tunneling between Be acceptor 1s(3/2) (Gamma(6) + Gamma(7)) energy level in the middle quantum-well and the band in the left-side non-doping quantum-well, as well as the resonant tunneling between the HH hand in the right-side non-doping quantum-well and Be acceptor 2p(5/2) (Gamma(6) + Gamma(7)) energy level