The disclosure provides an optical waveguide, a manufacturing method of an optical waveguide, and a head-mounted display device. The optical waveguide has a first optical region and a second optical region for transmitting an image beam. The optical waveguide includes a plate body, multiple first light-guiding optical elements, and multiple optical microstructures. The first light-guiding optical elements are disposed in parallel lines on a light-guiding plane inside the plate body. The light-guiding plane is located in the first optical region, and there is a spacing between the adjacent first light-guiding optical elements. The image beam transmitted to the light-guiding plane is separated into multiple sub image beams, and the transmission paths of the sub image beams are at least partially different. The optical coupling-out structure is disposed in the plate body and is located in the second optical region.

Structures and methods for high speed interconnection in photonic systems are described herein. In one embodiment, a photonic device is disclosed. The photonic device includes: a substrate; a plurality of metal layers on the substrate; a photonic material layer comprising graphene over the plurality of metal layers; and an optical routing layer comprising a waveguide on the photonic material layer.

In a method for depositing a layer of amorphous hydrogenated silicon carbide (SiC:H), a gas mixture comprising a reactive gas to inert gas volume ratio of 1:12 to 2:3 is introduced into a reaction chamber of a plasma-enhanced chemical vapor deposition apparatus. The reactive gas has a ratio of Si of 50 to 60, C of 3 to 13, and H of 32 to 42 at %. The inert gas comprises i) a first inert gas selected from helium, neon and mixtures; and ii) a second inert gas selected from argon, krypton, xenon and mixtures. The reaction plasma is at a power frequency of 1-16 MHz at a power level of 100 W to 700 W. The resulting layer exhibits a refractive index of not less than 2.4 and a loss of not more than 180 dB/cm at an indicated wavelength within 800 to 900 nm.

Various polarization rotator splitter (PRS) configurations are disclosed. In an example embodiment, a system includes a PRS that includes a silicon nitride (SiN) rib waveguide core that includes a rib and a ridge that extends vertically above the rib, the SiN rib waveguide core having a total height h.sub.SiN from a bottom of the rib to a top of the ridge, a rib height h.sub.rib from the bottom of the rib to a top of the rib, a rib width w.sub.rib, and a top width w.sub.SiN of the ridge. The rib width w.sub.rib varies along at least a portion of a length of the SiN rib waveguide core.

The invention relates to a method for manufacturing a waveguide (2a, 2b) comprising: A supplying of a substrate (1) comprising a stack of a first layer (11) based on a first material on a second layer (12) based on a second material, and at least one sequence successively comprising: An etching of the first material, in such a way as to define at least one pattern (20, 22a) having etching flanks (200, 201), A smoothing annealing assisted by hydrogen in such a way as to smooth the etching flanks (200, 201) of the at least one pattern (20, 22a), A re-epitaxy of the first material on the pattern (20, 22a) based on the first material

A semiconductor device is provided. The semiconductor device includes a silicon nitride waveguide in a first dielectric layer over a substrate. The semiconductor device includes a semiconductor waveguide in a second dielectric layer over the first dielectric layer. The first dielectric layer including the silicon nitride waveguide is between the second dielectric layer including the semiconductor waveguide and the substrate.

An apparatus includes a photonic integrated circuit having an optical phased array, where the optical phased array includes multiple unit cells. Each unit cell includes at least one antenna element configured to transmit or receive multiple optical signals having spectrally-distinct wavelengths or wavelength ranges. Each unit cell also includes at least one signal pathway configured to transport the optical signals to or from the at least one antenna element. Each unit cell further includes a phase modulator configured to modify phases of the optical signals being transported through the at least one signal pathway. Each unit cell is configured to provide correlated phase shifts to the optical signals having the spectrally-distinct wavelengths or wavelength ranges.

Disclosed herein are configurations and methods to produce very low loss waveguide structures, which can be single-layer or multi-layer. These waveguide structures can be used as a sensing component of a small-footprint integrated optical gyroscope. By using pure fused silica substrates as both top and bottom cladding around a SiN waveguide core, the propagation loss can be well below 0.1 db/meter. Low-loss waveguide-based gyro coils may be patterned in the shape of a spiral (circular or rectangular or any other shape), that may be distributed among one or more of vertical planes to increase the length of the optical path while avoiding the increased loss caused by intersecting waveguides in the state-of-the-art designs. Low-loss adiabatic tapers may be used for a coil formed in a single layer where an output waveguide crosses the turns of the spiraling coil.

Disclosed herein are configurations and methods to produce very low loss waveguide structures, which can be single-layer or multi-layer. These waveguide structures can be used as a sensing component of a small-footprint integrated optical gyroscope. By using pure fused silica substrates as both top and bottom cladding around a SiN waveguide core, the propagation loss can be well below 0.1 db/meter. Low-loss waveguide-based gyro coils may be patterned in the shape of a spiral (circular or rectangular or any other shape), that may be distributed among one or more of vertical planes to increase the length of the optical path while avoiding the increased loss caused by intersecting waveguides in the state-of-the-art designs. Low-loss adiabatic tapers may be used for a coil formed in a single layer where an output waveguide crosses the turns of the spiraling coil.

An example device in accordance with an aspect of the present disclosure includes a diamond waveguide disposed on a substrate. The substrate includes a dielectric material. A tuner is to extend from the substrate, and is disposed at least in part over the waveguide. The tuner includes a tuner electrode to control a variable distance between the tuner and the waveguide to vary an effective refractive index of the waveguide.