Optical characterisation of InGaAs/InP and InGaAs/InGaAsP MQW structures for optoelectronic applications

We performed CW and time resolved photoluminescence (PL) measurements on on a series of conventional InGaI/InP MQW structures grown by low pressure metal organic vapor phase epitaxy (LP-MOVPE). Variation of sample temperature allows to distinct between regions with different well widths in CW experinments. The relative sizes of areas vith different well widths are determined. In time resolved PL experiments the carrier capture from the barriers into the quantum wells has been investigated. An ambipolar capture time constant of 5 ± 2 ps is evaluated. Finally the optical gain of these structures is compared with InGaAs/ InP- and InGaAsP/InP-MQW-separate-confinement structures.