Surface quantum wells

Abstract
Surface quantum wells of InP have been grown, by organometallic vapor phase epitaxy, on top of graded GaxIn1−xP epitaxial layers. The surface quantum well is confined on one side by vacuum, and on the other side by the graded GaxIn1−xP. Photoluminescence measurements show two transitions for electron‐hole recombination within the surface quantum well. Surface recombination appears to be saturated by the high density of carriers collected in the well, and plays a minor role. The bending of the conduction and valence bands in the GaxIn1−xP leads to a high collection efficiency of excess carriers near the surface, and suggests that high efficiency surface light emitters could be built in similar structures.