Optical Guided Wave Switching

Optical switching is a key functionality for enabling transparent all-optical networks. We present an overview of optical switching devices, based on either optical or electrical control signals, which permit to avoid the necessity of optics-electronics-optics conversion. We describe the basic principles of various guided wave optical switching devices, which exploit either relatively long interaction lengths in order to reduce the operating power requirements, or strong transverse confinement to reduce device dimensions. These devices include nonlinear mode couplers and interferometers based on optical fibers, as well as integrated waveguides based on photonic crystal structures or surface wave interactions in novel materials such as graphene.