Abstract

Much effort has been devoted to the realization of quantum-dot structures because of possible applications to lasers and other optical devices.¹ Recent progress in crystal- growth techniques has made it possible to realize quantum-dot structures as small as 15 nm.² Although the bottleneck that restricts a carrier's cascade down toward ground level through the emission of LO phonons has been pointed out,³ luminescence is clearly observed even in such small structures.

© 1995 Optical Society of America