High Desity and Compact Waveguide Using Ge on GaAs

9312726 Lu We propose to create Ge on GaAs waveguides in the mid infared. This novel waveguide offers high density and compact optical wiring in analogy with current electronic integrated circuits. High density is considered to be well over 10,000 components per square centimeter of surface. Optical wiring, or waveguides, are considered to be compact if their dimensions are much smaller than the wavelength. We are investigating here refractive index ratios of 4.0 to 1 with Ge waveguides confined by an air cladding. This high index ratio allows unprecedented control and confinement of the light. The problem in this approach is primarily one of design as tight confinement requires the waveguide component development to be rethought entirely in terms of waves rather than the usual paraxial ray optics. The use of high index ratios to create high confinement is applicable to all wavelenghts from microwave to the visible. We will perform our tests of components with microwave models, and create useful devices in the mid infrared using 10 micrometer wavelengths. The design results of the mid infrared components ae applicable to visible and near infrared integrated optics using, for instance, GaAs waveguides with AlAs cladding. ***