Optical waveguides are the basic components of the integrated optical circuits due to their compact size, high optical intensities, and enhanced performances with respect to the substrate materials. In nonlinear crystals, kinds of passive and active applications have been achieved benefiting from the optical guiding structures. This special issue aims to highlight recent research progresses in the field of optical waveguides for integrated nonlinear optics and the corresponding applications, including optical switches, modulators, amplifiers, and frequency converters.

We invite submissions of original research as well as review articles to this special issue.

Potential topics include but are not limited to the following:

• LiNbO₃-based waveguide devices for nonlinear optical applications
• Nonlinear optical phenomena in silicon waveguides
• Polymer-based optical waveguides and their nonlinear optical properties
• Novel techniques for fabrication and engineering of high-quality optical waveguides
• Nonlinearities in whispering-gallery-mode microcavities
• Optical waveguides for nonlinear wave mixing
• Novel photorefractive effect in optical waveguides
• Superlattice waveguide for nonlinear integrated optical devices
• New materials and configurations for nonlinear optics
• Supercontinuum generation in integrated optical waveguides
• IO in connecting light from lasers to fibers in multichannels for photonic packaging
• Optical frequency comb in optical waveguides