Abstract

The concept of giant oscillator strength for both free and bound excitons is elucidated. It is shown that, the oscillator strength of these transitions is enhanced over the free exciton oscillator strength per molecule of the crystal by the ratio of the volume of the system divided by the volume of the crystal unit cell. An expression for the free exciton oscillator strength is obtained that can be used to describe the AC Stark shift of an excitonic resonance and also its saturation behavior.

© 1988 Optical Society of America