Optical Properties of GAInAs/InP Multi-quantum Well Grown by Low Pressure MOVPE

Absorption, derivative absorption and reflectivity measurements have been performed on a series of GaInAs/InP multi-quantum well structures (MQWs) grown by low pressure (LP) metal organic vapor phase epitaxy (MOVPE). Excitonic transitions up to n=4 between confined states have been resolved and, in some cases, reveal clearly at room temperature. Comparison with previous photoluminescence (PL) data shows Stokes shifts as weak as 4 meV, indicating minor potential fluctuations. Each intrinsic excitonic transition energy is carefully determined by a series of theoretical fits in the light of the two-dimensional (2D) exciton model. The results reasonably agree with those expected from recent calculations without any adjustable parameter. Some departs of the alloy compositions or QW widths with respect to the nominal ones have been found. They result in a sizeable shift of the series of excitonic transitions with respect to their calculated positions.