LINEAR OPTICAL-PROPERTIES OF QUANTUM-WELLS COMPOSED OF ALL-BINARY INAS/GAAS SHORT-PERIOD STRAINED-LAYER SUPERLATTICES

The linear optical properties of a variety of (InAs/GaAs)-GaAs multiple quantum well structures, where each well consists of a highly strained InAs/GaAs short-period superlattice, have been investigated in detail. The results attest to the improvement in material quality over previously reported structures of this type. Clearly resolved excitonic absorption peaks have been observed at room temperature in all samples. Photoluminescence and excitonic absorption linewidths at 15 K are less than 10 meV in each case, with the photoluminescence Stokes shifted by less than 1 meV. Temporally resolved photoluminescence measurements at 15 K indicate carrier lifetimes of 1.4-1.8 ns. Dramatic strain-related differences are observed when compared to random alloy InGaAs/GaAs quantum wells with an equivalent average indium mole fraction.