A wavelength demultiplexer includes a photonic circuit and a control circuit that adjusts wavelength characteristics of the photonic circuit. The photonic circuit converts two orthogonal polarized waves contained in the incident light into two same polarized waves, which are supplied to a first optical demultiplexing circuit and a second optical demultiplexing circuit provided in the photonic circuit and having the same configuration. The photonic circuit supplies a total output power of monitor lights extracted from the same positions in the first optical demultiplexing circuit and the second optical demultiplexing circuit to the control circuit. The control circuit controls a first wavelength characteristic of the first optical demultiplexing circuit and a second wavelength characteristic of the second optical demultiplexing circuit based on the total output power of the monitor lights.

Electrical test of optical components via metal-insulator-semiconductor capacitor structures is provided via a plurality of optical devices including a first material embedded in a second material, wherein each optical device is associated with a different thickness range of a plurality of thickness ranges for the first material; a first capacitance measurement point including the first material embedded in the second material; and a second capacitance measurement point including a region from which the first material has been replaced with the second material.

Method and apparatus for enhancing resolution in a light detection and ranging (LiDAR) system. In some embodiments, an emitter emits light in the form of multiplexed beams of randomized, multiple wavelengths across a field of view (FoV). A detector uses one or more detection channels to detect the multiplexed beams reflected from a target within the FoV to decode range information associated with the target. The multiplexed beams may be generated by multiple light sources such as laser diodes, or a single source such as a frequency comb device. Randomization may be applied via a pseudorandom bit sequence modulator, and multiplexing/demultiplexing may be performed using waveguides and micro-resonance rings (MRRs). The multiplexed beam may be emitted using an optical phase array (OPA) integrated circuit device to scan the FoV simultaneously using the different wavelengths. The range information can be used to adaptively adjust the wavelengths in a subsequent scan.

A two-channel photonic demultiplexer includes an input region to receive a multi-channel optical signal, two output regions, each adapted to receive a corresponding one of two distinct wavelength channels demultiplexed from the multi-channel optical signal, and a dispersive region including a first material and a second material inhomogeneously interspersed to form a plurality of interfaces that collectively structure the dispersive region to optically separate each of the two distinct wavelength channels from the multi-channel optical signal and respectively guide the first distinct wavelength channel to a first output region and the second distinct wavelength channel to the second output region when the input region receives the multi-channel optical signal. At least one of the first material or the second material is structured within the dispersive region to be schematically reproducible by a feature shape with a pre-determined width.

Structures for a wavelength division multiplexing filter and methods of fabricating a structure for a wavelength division multiplexing filter. The structure includes a first waveguide core having a first section and a second section. The first section and the second section have a first notched sidewall and a second notched sidewall opposite to the first notched sidewall. The structure further includes a second waveguide core positioned with a first offset in a first direction relative to the first section and the second section of the first waveguide core and with a second offset in a second direction relative to the first section and the second section of the first waveguide core. The second direction is transverse to the first direction.

A Mach-Zehnder interferometer (MZI) filter comprising one or more passive compensation structures are described. The passive compensation structures yield MZI filters that are intrinsically tolerant to perturbations in waveguide dimensions and/or other ambient conditions. The use of n+1 waveguide widths can mitigate n different sources of perturbation to the filter. The use of at least three different waveguide widths for each Mach-Zehnder waveguide can alleviate sensitivity of filter performance to random width or temperature variations. A tolerance compensation portion is positioned between a first coupler section and a second coupler section, wherein the tolerance compensation portion includes a first compensation section having a second width, a second compensation section having a third width and a third compensation section having a fourth width, wherein the fourth width is greater than the third width and the third width is greater than the second width.

Examples disclosed herein relate to quantum-dot (QD) photonics. In accordance with some of the examples disclosed herein, a QD semiconductor optical amplifier (SOA) may include a silicon substrate and a QD layer above the silicon substrate. The QD layer may include an active gain region to amplify a lasing mode received from an optical signal generator. The QD layer may have a gain recovery time such that the active gain region amplifies the received lasing mode without pattern effects. A waveguide may be included in an upper silicon layer of the silicon substrate. The waveguide may include a mode converter to facilitate optical coupling of the received lasing mode between the QD layer and the waveguide.

A waveguide illuminator includes an input waveguide, a waveguide splitter coupled to the input waveguide, and a waveguide array coupled to the waveguide splitter. The waveguide array includes an array of out-couplers out-coupling portions of the split light beam to form an array of out-coupled beam portions for illuminating a display panel. To reduce optical interference, the waveguide illuminator may have two interlaced waveguide arrays energized by two different light sources. Output polarizations of neighboring light pixels of a display illuminated with such waveguide illuminator may be orthogonal to each other. The frames to be displayed may be broken down into sequentially displayed sub-frames with interleaved pixels.

A thermally tunable waveguide including an optical waveguide and a heater is provided. The optical waveguide includes a phase shifter. The heater is disposed over the optical waveguide. The heater includes a heating portion, pad portions and tapered portions. The heating portion overlaps with the phase shifter of the optical waveguide. The pad portions are disposed aside of the heating portion. Each of the pad portions is connected to the heating portion through one of the tapered portions respectively.

Described herein are photonic integrated circuits (PICs) comprising a semiconductor optical amplifier (SOA) to output a signal comprising a plurality of wavelengths, a sensor to detect data associated with a power value of each wavelength of the output signal of the SOA, a filter to filter power values of one or more of the wavelengths of the output signal of the SOA, and control circuitry to control the filter to reduce a difference between a pre-determined power value of each filtered wavelength of the output signal of the SOA and the detected power value of each filtered wavelength of the output signal of the SOA.