Abstract

Restriction of excitons in semiconductor structures of reduced dimensionality results in increased oscillator strength in the excitonic absorption, which can be exploited in the design of nonlinear optical devices.¹ We report transient bleaching studies of CdSe quantum dots whose size (35 Å) is small compared to the exciton radius in bulk CdSe. The clusters are grown by a new synthetic method,² which results in high quantum yield of band edge luminescence, low saturation intensities (~100 μj/cm²), and long bleaching recovery times (nanoseconds). Most of our measurements are done at 25 K in dilute glasses containing the clusters.

© 1990 Optical Society of America