An optical switch device includes a first semiconductor structure configured to operate as a first waveguide and a second semiconductor structure configured to operate as a second waveguide. The second semiconductor structure is located above or below the first semiconductor structure and separated from the first semiconductor structure. The second semiconductor structure includes a first portion having a first width and a second portion having a width different from the first width and located on the first portion. The first portion is located between a first doped region and a second doped region.

Embodiments of the disclosure provide an optical antenna for a photonic integrated circuit (PIC). The optical antenna includes a vertically oriented semiconductor waveguide with a first end on a semiconductor layer. The vertically oriented semiconductor waveguide includes a first sidewall and a second sidewall opposite the first sidewall. A reflective material is along the second sidewall of the vertically oriented semiconductor waveguide. A first plurality of grating protrusions extends from the first sidewall of the vertically oriented semiconductor waveguide.

An electro-optical chip includes an optical input port, an optical output port, and an optical waveguide having a first end optically connected to the optical input port and a second end optically connected to the optical output port. The optical waveguide includes one or more segments. Different segments of the optical waveguide extends in either a horizontal direction, a vertical direction, a direction between horizontal and vertical, or a curved direction. The electro-optical chip also includes a plurality of optical microring resonators is positioned along at least one segment of the optical waveguide. Each microring resonator of the plurality of optical microring resonators is optically coupled to a different location along the optical waveguide. The electro-optical chip also includes electronic circuitry for controlling a resonant wavelength of each microring resonator of the plurality of optical microring resonators.

A cavity substrate may have a directional optoelectronic transmission channel. The cavity substrate includes a support frame, a first dielectric layer on a first surface of the support frame, and a second dielectric layer on a second surface of the support frame. The support frame, the first dielectric layer and the second dielectric layer constitute a closed cavity having an opening on one side in the length direction of the substrate, a first circuit layer is arranged on the inner surface of the first dielectric layer facing the cavity, an electrode connected with an optical communication device is arranged on the first circuit layer, the electrode is electrically conducted with the first circuit layer, a second circuit layer is arranged on the outer surfaces of the first dielectric layer and the second dielectric layer, and the first circuit layer and the second circuit layer are communicated through a via column.

A waveguide grating. The waveguide grating includes a rib composed of a first material. A first portion of the waveguide has a first layer on the rib, the first layer being composed of a second material; and a second layer on the first layer, the second layer being composed of a third material, the third material having a higher index of refraction than the first material.

An integrated optical beam steering device includes a planar Luneburg lens that collimates beams from different inputs in different directions within the lens plane. It also includes a curved (e.g., semi-circular or arced) grating coupler that diffracts the collimated beams out of the lens plane. The beams can be steered in the plane by controlling the direction along which the lens is illuminated and out of the plane by varying the beam wavelength. Unlike other beam steering devices, this device can operate over an extremely wide field of view—up to 180°—without any aberrations off boresight. In other words, the beam quality is uniform in all directions, unlike with aplanatic lenses, thanks to the circular symmetry of the planar Luneburg lens, which may be composed of subwavelength features. The lens is also robust to misalignment and fabrication imperfections and can be made using standard CMOS processes.

A disclosed multimode optical fiber comprises a core and a cladding surrounding the core. The core has an outer radius r.sub.1 in between 20 μm and 30 μm. The cladding includes a first outer cladding region having an outer radius r.sub.4a and a second outer cladding region having an outer radius r.sub.4b less than or equal to 45 μm. The second outer cladding region comprises silica-based glass doped with titania. The optical fiber further includes a primary coating with an outer radius r.sub.5 less than or equal to 80 μm, and a thickness (r.sub.5−r.sub.4) less than or equal to 30 μm. The optical fiber further includes a secondary coating with an outer radius r.sub.6 less than or equal to 100 μm. The secondary coating has a thickness (r.sub.6−r.sub.5) less than or equal to 30 μm, and a normalized puncture load greater than 3.6×10.sup.−3 g/micron.sup.2.

An implantable optical sensor (1) comprising a substrate (2) and at least one optical microstructure (3) for evanescent field sensing integrated with the substrate (2), the at least one optical microstructure (3) being positioned to form an optical interaction area (4) on a part of a surface (5) of the substrate (2), the optical assembly (1) further comprising a thin protective layer (6) covering at least the optical interaction area (4), the thin protective layer (6) being in a predetermined material with corrosion-protection characteristics and having a predetermined thickness, so as not to affect the evanescent field sensing.

Described herein are hybrid IC assemblies that include multiple stacked layers of electronic and/or photonic circuit elements. For example, a first layer of the IC assembly includes a waveguide formed of a substantially monocrystalline material, and a second layer of the IC assembly includes at least one electronic circuit element. A bonding material between a front face of the first layer and a back face of the second layer attaches the first layer to the second layer. The bonding material has a lower crystallinity than the waveguide.

A method to form a three-dimensional photonic crystal template with a gradient structure involves irradiating a photoresist composition of a thickness of at least 15 μm from at least four laser beams to yield a periodic patterned with a percolating matrix of mass in constructive volumes of a cured photoresist composition and destructive volumes of voids free of condensed matter where the proportion of constructive volume displays a gradient from the irradiated surface to the substrate after development. For a given light intensity, photoinitiator concentration in the photoresist composition, and a given thickness, by irradiating for a relatively short period, a three-dimensional photonic crystal template displaying a gradient having greater constructive volume proximal the air interface forms and a relatively long irradiation period results in a gradient having greater constructive volume proximal the substrate.