Vol. 42, Issue 4, pp. 821-828 (2012)

Abstract

All-optical switching in Bragg-spaced quantum well contained uniform quantum dots (QDs) is investigated in theory. With our design, it is nonresonant excitation for pumping a few meV below the photonic band-gap. The active photonic band-gap structure is shifted by the optical Stark effect, and the circular dichroism and birefringence are induced by the circular polarized pump light. Thus, the optical switching can be realized based on the ultrafast nonlinear effect. The switch, with great advantages of lower requirement of pump light intensity and high contrast ratio, is a promising candidate for the ultrafast all-optical switching devices in future.