BELOW-GAP LIGHT-EMISSION FROM TYPE-II HETEROINTERFACE OF IN0.52AL0.48AS INP SYSTEM GROWN ON (111)B AND (100)INP SUBSTRATES/

Temperature and excitation power dependence of the below-gap emission from type II heterointerface was studied for InAlAs/InP type II hetero structures grown on (111)B and (100) InP substrates. It was found that below 30 K, the photoluminescence (PL) intensity of the type II emiss ion of the (111)B sample was comparable to that of the (100) sample, b ut was 20 times stronger than that of the (100) sample at room tempera ture. The excitation power dependence of the PL intensity shows that t he PL intensity ratio between the (111)B sample and the (100) sample d ecreases with increasing excitation power. These results can be unders tood by assuming smaller nonradiative recombination centers at the (11 1)B heterointerface. (C) 1998 Elsevier Science B.V. All rights reserve d.