Abstract: An optical performance monitor for measuring the performance of optical networks has an echelle grating for demultiplexing an input beam into a plurality of wavelengths that are focused onto an array of divided output waveguides. Each divided output waveguide is positioned to receive a corresponding demultiplexed wavelength from the echelle grating or other waveguide multiplexer device. The divided output waveguides laterally separate the corresponding demultiplexed wavelength into a first and second portions. A detector array is positioned to receive the respective portions of the demultiplexed wavelengths and by comparing their relative intensity it is possible to detect any drift in the nominal wavelengths of the channels.

Abstract: According to this invention, silicon-based photodetectors using waveguides formed with silicide regions can have high speed and high efficiency for near IR applications. Utilizing the unique properties of suicides, the proposed method provides a simple and elegant way to implement a photodetector design in which photogenerated carriers travel perpendicular to the direction of light propagation. Therefore, the speed and quantum efficiency of the photodetector may be optimized independently. This device configuration may be implemented in one of the two approaches: (a) waveguides formed through surface silicidation of a silicon-based layer of a substrate (b) waveguides formed through silicidation of ridge waveguide side-walls of a silicon-based layer of a substrate; The use of mature silicon technology promises low cost of production and other benefits.

Abstract: In order to fabricate a photonic device with an enhanced photoresponse at 155 nm, a plurality of undulating quantum well layers are grown on said substrate in a three dimensional growth mode to defeat the limitations imposed by strain on the maximum layer thickness. The quantum wells typically are formed by epitaxially growing alternating layers of Si1−x,Gex, and Si on a silicon substrate.