Absorption spectroscopy on Ga 0.47 In 0.53 As/ Al 0.48 In 0.52 As multi-quantum-well heterostructures. II. Subband structure

摘要: The subband structure of ${\mathrm{Ga}}_{0.47}$${\mathrm{In}}_{0.53}$As/${\mathrm{Al}}_{0.48}$${\mathrm{In}}_{0.52}$As multi-quantum-well heterostructures (MQWH's) lattice matched to InP, grown by molecular-beam epitaxy, was determined absorption and magnetoabsorption experiments for well widths ranging from 2.3 13.8 nm. A comparison theoretical models (parabolic single-band coupled six-band envelope-function approximations) reveals the necessity taking nonparabolicity conduction band as all valence subbands into account. equal values reduced effective mass electron mass, obtained Shubnikov\char21{}de Haas cyclotron-resonance experiments, show that highest valence-subband is much larger than assumption decoupled subbands. In view complete best description given using a conduction-band offset \ensuremath{\Delta}${E}_{c}$=500 meV capacitance-voltage measurements in literature. For this value calculated transition energies are about 10% higher experimental results.