Abstract: An integrated optical waveguide includes a substrate, a waveguide under-cladding layer disposed on the substrate, and a waveguide core, having top and sidewall surfaces, disposed on the under-cladding layer. A glassy surface smoothing layer disposed on the waveguide core top surface and sidewall surfaces and has a refractive index, relative to a refractive index of the waveguide core, that enables guided optical transmission through the waveguide core and the glassy surface smoothing layer. In fabrication of the optical waveguide, a waveguide under-cladding layer is formed on a substrate and a waveguide core having sidewall surfaces and a top surface is formed on the under-cladding layer. A liquid suspension comprising particles of a glassy material is applied on the top and sidewall surfaces of the waveguide core. The applied liquid glassy particle suspension is heated to form a glassy surface smoothing layer on the waveguide core top surface and sidewall surfaces.

Abstract: A lateral photodiode, with improved response speed, includes a semiconductor substrate having active regions, and a p-type region and an n-type region arranged parallel to the surface of the substrate. The active regions are an n-layer and a p-layer respectively, and stacked in the thickness direction of the substrate to form a p-n junction. In addition, a barrier layer, for preventing movement of carriers from the substrate toward the active region, is provided on the side of the active regions toward the substrate.

Abstract: A multispectral pixel structure is provided that includes a plurality of stacked cavity arrangements for emitting or detecting a plurality of specified wavelengths, wherein each stacked cavity arrangement having a photoactive layer for spectral emission or detection of one of the specified wavelengths. The photoactive layer is positioned within a resonant cavity stack and the resonant cavity stack being positioned between two adjacent mirror stacks. A plurality of coupling-matching layers are positioned between one or more of the stack mirror arrangements for controlling optical phase and coupling strength between emitted or incident light and resonant modes in each of the stacked cavity arrangements.

Abstract: A surface plasmon polariton (SPP) pixel structure is provided. The SPP pixel structure includes a coupling structure that couples the probing light into the SPP mode by matching the in-plane wave vector by changing the refractive index of the coupling structure using thermo-optic effects to vary the coupling strength of the probing light into the SPP mode. An absorber layer is positioned on the coupling structure for absorbing incident infrared/thermal radiation being detected.

Abstract: A method of manufacturing a photovoltaic cell includes providing an active absorption layer, forming a pseudo-periodic grating adjacent to the active absorption layer, and forming a reflector adjacent to the pseudo-periodic grating. A photovoltaic cell includes an active absorption layer, a pseudo-periodic grating adjacent to the active absorption layer, and a reflector adjacent to the pseudo-periodic grating.

Abstract: An optical modulator structure includes at least two waveguide structures for inputting and outputting an optical signal. At least one ring resonator structure provides coupling between the at least two waveguide structures. The at least one ring resonator structure includes Ge or SiGe.

Abstract: The invention provides a waveguide with a waveguide core having longitudinal sidewall surfaces, a longitudinal top surface, and a longitudinal bottom surface that is disposed on a substrate. An interface layer is disposed on at least one longitudinal sidewall surface of the waveguide core. A waveguide cladding layer is disposed on at least the waveguide core sidewall and top surfaces, over the interface layer. The waveguide of the invention can be produced by forming a waveguide undercladding layer on a substrate, and then forming a waveguide core on the undercladding layer. An interface layer is then formed on at least a longitudinal sidewall surface of the waveguide core, and an upper cladding layer is formed on a longitudinal top surface and on longitudinal sidewall surfaces of the waveguide core, over the interface layer.

Abstract: A magneto-optical isolator device is provided. The isolator device includes a substrate and a bottom cladding layer that is formed on the substrate. An optical resonator structure is formed on the bottom cladding layer. The resonator structure includes crystalline or amorphous diamagnetic silicon or silicon-germanium so as to provide non-reciprocal optical isolation. A top cladding layer is formed on the resonator structure. One or more magnetic layers positioned on the top cladding layer or between the top cladding or bottom cladding layers and the optical resonator structure.

Abstract: A method of forming a low loss crystal quality waveguide is provided. The method includes providing a substrate and forming a dielectric layer on the substrate. A channel is formed by etching a portion of the dielectric layer. A selective growth of a Si Ge, or SiGe layer is performed in the area that defines the channel. Furthermore, the method includes thermally annealing the waveguide at a defined temperature range.

Abstract: An on-chip amplifier includes first element that curtails the velocity of an incoming light to the amplifier. A second element is doped so as to make the frequency of the incoming light equal to the electron frequency in order to allow for electron-photon wave interaction, so that when current flows through the amplifier, electron power is transferred to the incoming light, resulting in amplification of the incoming light.

Abstract: An infrared photodiode structure is provided. The infrared photodiode structure includes a doped semiconductor layer having ions of certain conductivity. An active photodetecting region is positioned on the doped semiconductor layer for detecting an infrared light signal. The active photodetecting region includes one or more amorphous semiconductor materials so as to allow for high signal-to-noise ratio being achieved by invoking carrier hopping and band conduction, under dark and illuminated conditions.

Abstract: A surface plasmon polariton (SPP) pixel structure is provided. The SPP pixel structure includes a coupling structure that couples the probing light into the SPP mode by matching the in-plane wave vector by changing the refractive index of the coupling structure using thermo-optic effects to vary the coupling strength of the probing light into the SPP mode. An absorber layer is positioned on the coupling structure for absorbing incident infrared/thermal radiation being detected.

Abstract: A waveguide structure includes a SOI substrate. A core structure is formed on the SOI substrate comprising a plurality of multilayers having alternating or aperiodically distributed thin layers of either Si-rich oxide (SRO), Si-rich nitride (SRN) or Si-rich oxynitride (SRON). The multilayers are doped with a rare earth material so as to extend the emission range of the waveguide structure to the near infrared region. A low index cladding includes conductive oxides to act as electrodes.

Abstract: A photodiode in which increased sensitivity and speed are balanced. The photodiode includes: a semiconductor substrate; a plurality of active regions formed on the substrate by selective epitaxial growth; and a comb electrode provided for each of the plurality of active regions and in communication with each other to electrically connect the active regions together.

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 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: An optical amplifier on a silicon platform includes a first doped device layer and a second doped device layer. A gain medium is positioned between the first and second doped device layers. The gain medium comprises extrinsic gain materials so as to substantially confine in the gain medium a light signal and allow the optical amplifier to be electrically or optically pumped.

Abstract: A photodiode balanced in increased sensitivity and speed. The photodiode includes a semiconductor substrate, an active region formed on the semiconductor substrate, and a comb electrode connected to the active region. The comb electrode includes a plurality of electrode fingers, and each of the electrode fingers includes a transparent electrode contacting the active region, and an opaque electrode formed on the transparent electrode. Here, the width of the opaque electrode is set smaller than the width of the transparent electrode.

Abstract: A bidirectional transceiver assembly includes a VCSEL structure that emits light at a defined wavelength on a substrate structure. A photodetector receives the light. A hole structure is formed on the substrate structure to allow the light from the VCSEL structure to be emitted so as to form an optical path.

Abstract: A planar mid-infrared (mid-IR) integrated microphotonic platform includes at least one laser performing lasing functions. The at least one laser comprises chalcogenide glass. At least amplifier structure is coupled to the at least one laser for performing optical amplification. The at least amplifier structure comprises chalcogenide glass. At least one waveguide structure is coupled to the at least one amplifier structure for guiding an optical signal in the microphotonic platform. The at least waveguide structure comprises chalcogenide glass. At least one modulator structure is coupled to the at least one waveguide structure for modulating the optical signal. The at least modulator structure comprises chalcogenide glass. At least one photodetector is coupled to the at least one modulator structure for performing photodetecting functions of the microphotonic platform. The at least photodetector comprises chalcogenide glass.