Abstract: A solar cell includes a photoactive region that receives light. A photonic crystal is coupled to the photoactive region, wherein the photonic crystal comprises a distributed Bragg reflector (DBR) for trapping the light.

Abstract: An optical grating is disposed on a waveguide to redirect light from the interior of the waveguide through the opposite side of the waveguide from the grating. In one embodiment the waveguide, the grating, and an optical sensor are combined in a single monolithic structure. In another embodiment, an absorbing layer is directly connected to the waveguide in the region of the grating. In still another embodiment, efficiency of the grating is improved by having a high index contrast between the refractive index of the grating and the refractive index of the cladding disposed over the grating, and by having an appropriately sized discontinuity in the grating.

Abstract: A fabrication method produces Si compatible light-emitting materials showing sizeable optical gain by thermally annealing thin film layers of Si-rich nitride (SiNx) By utilizing the Si compatible light-emitting material, light emitting devices can be fabricated that are compatible with CMOS processes. The Si compatible light-emitting material is a high index (refractive index ranging from 1.6 to 2.3) material allowing flexible design of high confinements photonic devices with strong structural stability with respect to annealing treatments. The Si compatible light-emitting material realizes broad band light emission by allowing resonant coupling with rare earth atoms and other infrared emitting quantum dots and better electrical conduction properties with respect to SiO2 systems. The Si compatible light-emitting material also realizes high transparency (low pumping and modal losses) in the visible range.

Abstract: A thin film quaternary compound semiconductor comprising arsenic (As), selenium (Se), tellurium (Te) and copper (Cu) atoms with adjustable molar concentrations during processing, whose atomic arrangement is predominantly amorphous, glassy or polycrystalline, and dominated by covalent chemical bonds between the said atoms. The amorphous nature of the atomic arrangement gives predominance to short range atomic order, eliminating the constraints of lattice constant mismatch and polarity mismatch with the substrate, which opens the way to wide chemical compositional adjustments and to lower-cost deposition processes such as thermal evaporation or sputtering.

Abstract: A novel detection pixel micro-structure allowing the simultaneous and continuous detection of several discrete optical frequencies. A focal plane array comprises a plurality of multi-spectral detection pixels and a connecting platform to electrically connect the pixels. Each of the multi-spectral detection pixels form a resonant optical structure that comprises at least two periodic latticed dielectric reflectors, and at least one optical cavity between the said latticed dielectric reflectors. The latticed dielectric reflectors create a plurality of photonic bandgaps in the spectral response of the pixel. In addition, each optical cavity of the pixel comprises at least two optical resonant modes, corresponding to localized Bloch modes supported by the pixel dielectric structure, wherein each optical resonant mode is localized maximally at, and minimally away from, the optical cavity.

Abstract: A waveguide structure includes a core structure that has low index materials. A photonic crystal cladding structure utilized in guiding optical modes in the core. The photonic crystal cladding structure includes alternating layers of Si and Si3N4.

Abstract: A phototransistor includes an emitter and a base that comprises Ge. A collector comprises Si. The base, emitter, and collector form at least one Si/Ge heterojunction allowing the unpinning of Fermi energy level (EF) of the phototransistor.

Abstract: An optical device includes a first and a second splitting device. Each of the first and second splitting devices have respective first and second input ports, respective first and second output ports, and a respective transfer matrix. A first optical waveguide is optically coupled to the first output port of the first splitting device and the first input port of the second splitting device. A second optical waveguide is optically coupled to the second output port of the first splitting device and the second input port of the second splitting device. The first and second optical waveguides are configured to introduce a phase shift of ? radians to the optical radiation propagating through the first optical waveguide with respect to the optical radiation propagating through the second optical waveguide.

Abstract: An optical device includes at least two photonic bandgap crystal (PBG) stacks that are each comprised of alternating layers of high and low index materials. A defect region is formed in a cavity region between the at least two photonic bandgap crystal stacks so as to provide the properties needed to reflect light received by the optical device.

Abstract: A fabrication method and materials produce high quality aperiodic photonic structures. Light emission can be activated by thermal annealing post growth treatments when thin film layers of SiO2 and SiNx or Si-rich oxide are used. From these aperiodic structures, that can be obtained in different vertical and planar device geometries, the presence of aperiodic order in a photonic device provides strong group velocity reduction (slow photons), enhanced light-matter interaction, light emission enhancement, gain enhancement, and/or nonlinear optical properties enhancement.

Abstract: An optical switch includes at least two signal bus waveguides that receive optical signals as input. At least two directional couplers are positioned so that the inputs to the at least two directional couplers are not switched relative to each other.

Abstract: An optical switch includes at least two signal bus waveguides that receive optical signals as input. At least two directional couplers are positioned so that the inputs to the at least two directional couplers are not switched relative to each other.

Abstract: A system is disclosed for providing electrical power responsive to solar energy. The system includes a Si cell, an AlGaAs cell, and a Ge cell. The Si cell is for providing electrical power responsive to solar energy within a first frequency range. The AlGaAs cell is coupled to a first side of the Si cell, and is for providing electrical power responsive to solar energy within a second frequency range. The Ge cell is coupled to a second side of the Si cell, and the Ge cell provides electrical power responsive to solar energy within a third frequency range.

Abstract: A microphotonic light source includes an optical pump and a plurality of waveguides that distribute optical pump power of the optical pump. At least one Erbium-doped laser ring is coupled to at least one of the waveguides so as to match the resonance condition of the optical pump.

Abstract: An optical structure includes a substrate having two side surfaces. A first layer of high refractive index material is formed on the substrate. A sacrificial layer is formed on the first layer. A second layer of high refractive index material is formed on the sacrificial layer. At a predefined temperature the sacrificial layer is evaporated, thus forming an air gap between the first layer and the second layer.

Abstract: A photodetector device includes a plurality of Ge epilayers that are grown on a substrate and annealed in a defined temperature range. The Ge epilayers form a tensile strained Ge layer that allows the photodetector device to operate efficiently in the C-band and L-band.

Abstract: The light-guiding structure includes a waveguide structure that comprises a substrate and a low refractive index underclad material. The waveguide structure is oxidized to form an oxidized layer on a surface of the waveguide structure. The oxidized layer is isotropically etched after the reaction-limited oxidation regime is approaching the diffusion-limited regime and repeatedly oxidized and etched so that the waveguide structure is continuously oxidized in the reaction-limited regime, reducing the overall time of oxidation and volume of oxidized material so that the waveguide structure has its sidewall roughness reduced efficiently enabling high transmission rates of guided light.