Abstract: Light recycling within a waveguide is achieved by mode conversion instead of resonance. A structure is provided in in which light makes multiple passes through the same waveguide by converting the mode to a different mode after each pass and rerouting the light back into the same waveguide. The structure includes a bus waveguide and at least one mode converter device disposed at or adjacent each of two opposing ends of the bus waveguide, wherein each mode converter devices is configured to receive light having a receiving mode along a first direction and to cause light having a different mode from the receiving mode to propagate in a second direction opposite the first direction.

Abstract: A method of forming an emitting array of waveguides, comprising providing a plurality of waveguides that exhibit different propagation constants so as to ensure that nearby waveguides do not couple evenly over parallel propagation lengths by varying a length in one or more dimensions of respective waveguides, whereby the respective waveguides are phasemismatched with at least their nearest neighbor.

Abstract: An optical coupling apparatus comprising a substrate having a trench formed therein, the trench having a width measured between two opposing walls that define a portion of the trench; and a waveguide disposed on or in the substrate, the waveguide having a width that tapers along an axis of light propagation.

Abstract: A probe structure includes a monolithically integrated waveguide and lens. The probe is based on SU-8 as a guiding material. A waveguide mold is defined using wet etching of silicon using a silicon dioxide mask patterned with 45° angle with respect to the silicon substrate edge and an aluminum layer acting as a mirror is deposited on the silicon substrate. A lens mold is made using isotropic etching of the fused silica substrate and then aligned to the silicon substrate. A waveguide polymer such as SU-8 2025 is flowed into the waveguide mask+lens mold (both on the same substrate) by decreasing its viscosity and using capillary forces via careful temperature control of the substrate.

Abstract: This patent document provides optical processing and switching of optical channels based on mode-division multiplexing (MDM) and wavelength division multiplexing (WDM).

Abstract: A millimeter scale weak grating coupler comprising a silicon waveguide having bars of overlay material of length (a) disposed periodically at a period (?) adjacent the silicon waveguide whereby a uniform grating output is achieved.

Abstract: A cryogenic optoelectronic data link, comprising a sending module operating at a cryogenic temperature less than 100 K. An ultrasensitive electro-optic modulator, sensitive to input voltages of less than 10 mV, may include at least one optically active layer of graphene, which may be part of a microscale resonator, which in turn may be integrated with an optical waveguide or an optical fiber. The optoelectronic data link enables optical output of weak electrical signals from superconducting or other cryogenic electronic devices in either digital or analog form. The modulator may be integrated on the same chip as the cryogenic electrical devices. A plurality of cryogenic electrical devices may generate a plurality of electrical signals, each coupled to its own modulator. The plurality of modulators may be resonant at different frequencies, and coupled to a common optical output line to transmit a combined wavelength-division-multiplexed (WDM) optical signal.

Abstract: There is set forth herein an optomechanical device which can comprise a first mirror and a second mirror forming with the first mirror a cavity. In one aspect the first mirror can be a movable mirror. The optomechanical device can be adapted so that the first mirror is moveable responsively to radiation force.

Abstract: An optical apparatus for coupling an optical fiber to a waveguide is disclosed. The optical apparatus can comprise a funnel coupler having an orifice configured to receive an optical fiber. The funnel coupler can mechanically support the optical fiber when received in the orifice. The funnel coupler can guide the optical fiber to a coupling end of the funnel coupler and a waveguide disposed adjacent the coupling end of the funnel coupler. One or more of the funnel coupler or the waveguide can be configured to optically couple the optical fiber and the waveguide when the optical fiber is received in the orifice.

Abstract: Provided are devices that have a distal portion configured to be implanted in a brain of a subject. The distal portion includes one or more emitters configured to emit light in the visible spectrum. The device includes a proximal portion configured to be external to the brain of the subject while the distal portion is implanted, wherein the proximal portion includes at least one waveguide in optical communication with the one or more emitters. The at least one waveguide defines a cross-sectional width less than 500 nm. The at least one waveguide is optionally coupled to a heating element that is optionally configured to adjust a phase of light within the at least one waveguide.

Abstract: Methods, systems, and devices are disclosed for implementing electro-optical modulators in which a resonating cavity structure is coupled to a transmission waveguide. In one example, the resonating structure includes a ring resonator whose coupling strength is controlled via an electrical control signal. The ring resonator is made of a capacitor comprising monolayer graphene sheets separated by a thick layer of dielectric material.

Abstract: Example methods, devices, and systems for optical transmission are disclosed. An example method can comprise coupling a plurality of optical filters to a substrate. The method can comprise coupling a polymeric waveguide to the plurality of optical filters. The polymeric waveguide can be configured to guide a free space optical signal along the polymeric waveguide and communicate, via the plurality of optical filters, one or more components of the free optical space signal to an integrated chip.

Abstract: A emitter is formed of a thin-film membrane disposed within a cavity so as to provide a output beam. The emitter may be configured to obtain broadband light. The emitter may enhance the emissivity of light over a broad spectral band.

Abstract: Methods, systems, and devices are described for electro-optic tuning. An example device may comprise a first layer comprising a transition metal di-chalcogenide material, a second layer comprising a conductive material, and a third layer comprising a dielectric material. The third layer may be disposed at least partially between the first layer and the second layer. An electrical potential difference applied between the first layer and the second layer may cause a tunable refractive index change in the first layer.

Abstract: Methods, systems, and devices are disclosed for implementing athermal optical devices based on composite structures having different components with different thermal properties such as a composite structure having materials of positive and negative thermo-optic effects or a composite structure having materials exhibiting different thermal expansion coefficients.

Abstract: Methods, systems, and devices are disclosed for using optical modes in optical waveguides to carry different optical communication signals. In one aspect, an optical device for optical MDM in optical communications includes an optical waveguide configured to support multiple optical waveguide modes and to carry light of different optical communication channels in different optical waveguide modes, respectively, of the multiple optical waveguide modes. The optical device includes an optical resonator configured to be capable of carrying an optical communication channel in one optical resonator mode and optically coupled to the optical waveguide to selectively couple the optical communication channel in the optical resonator into the optical waveguide to add a channel into the optical waveguide via optical mode division multiplexing. In another aspect, an optical mode division demultiplexing can be performed by coupling an optical waveguide and an optical resonator.

Abstract: Methods, systems, and devices are disclosed for linear optical phase modulators. In some aspects, a linear optical phase modulator device is provided to include a substrate; a PN junction formed on the substrate to include a P region, a N region and a depletion region formed by the P and N regions; and an optical waveguide formed on the substrate and structured to guide light in one or more optical modes to have a spatial optical intensity distribution based on a free carrier density spatial distribution in the PN junction in such that the depletion region exhibits a substantially linear response with regard to a voltage applied to the PN junction to modulate a phase of the light guided by the optical waveguide.

Abstract: This patent document provides optical processing and switching of optical channels based on mode-division multiplexing (MDM) and wavelength division multiplexing (WDM).

Abstract: Optical coupling designs are disclosed to provide a photonic device, for example, that includes a substrate; an optical waveguide formed on the substrate and configured as a multimode waveguide to support light in different optical waveguide modes; and an optical fiber structured as a multimode fiber to support light in different optical fiber modes, the optical fiber located above the optical waveguide and optically coupled to the optical waveguide via evanescent coupling to allow light to be coupled between the optical fiber and the optical waveguide.

Abstract: A emitter is formed of a thin-film membrane disposed within a cavity so as to provide a output beam. The emitter may be configured to obtain broadband light. The emitter may enhance the emissivity of light over a broad spectral band.