Large enhancement of optical nonlinearity using quantum dots embedded in a photonic crystal structure for all-optical switch applications

An ultrafast semiconductor all-optical switch using a third-order optical nonlinearity is attractive for a future OTDM system. This type of switch essentially requires both ultrafast and low optical-power operations. However, the tradeoff between them, based on the optical nonlinearity in general, often makes it difficult to achieve such a switch in practical use. This paper proposes a novel enhancement method of the third order nonlinearity by using quantum dots (QDs) embedded in a photonic crystal (PC), thus reducing the optical consumption power.