A multimode interference (MMI) coupler with an MMI region of curved edges, and a method of design and manufacturing by using a computerized optimization algorithm to determine a favorable set of segment widths for the MMI region for a predefined set of coupler design parameters.

Provided are a practical rib type optical waveguide in which polarization dependence and wavelength dependence and the like are small and an optical multiplexer/demultiplexer using the same. An optical waveguide type optical multiplexer/demultiplexer of the present invention includes a substrate, M input optical waveguides and N output optical waveguides including a single mode rib type optical waveguide, multi-mode optical interference regions including a rib type optical waveguide, and reversible tapered regions that smoothly connect the input/output optical waveguides to the multi-mode optical interference regions and include M×N rib type optical waveguides, and both side surfaces of the multi-mode optical interference region are respectively formed in a stepped shape.

There is provided an optical multiplexing and de-multiplexing element which is provided with a slab waveguide and a waveguide structure and can reduce radiation loss caused in a connection part between the slab waveguide and the waveguide structure. The waveguide structure includes a multimode interference (MMI) waveguide coupler and a narrow-width waveguide, the MMI waveguide coupler and the narrow-width waveguide are connected to each other in this order from a connection position with the slab waveguide along the waveguide direction, step portions are formed on both sides of the MMI waveguide coupler along the waveguide direction, and the thickness of the step portion is smaller than the thickness of the MMI waveguide coupler.

A coherent receiver comprising: a signal port receiving the signal light that has two polarization components at right angles each other; a polarization dependent beam splitter (PBS) that splits the signal light into two portions depending on the polarizations contained in the signal light; a beam splitter (BS) that splits the local light into two portions; a multi-mode interference (MMI) device that interferes between one of the two portions of the signal light and one of the two portions of the local light; optical components provided between the PBS and the MMI device; and wherein the PBS splitting a first wavelength range of the signal light and a second wavelength range outside the first wavelength range.

A silicon photonics based temperature-insensitive delay line interferometer (DLI). The DLI includes a first arm comprising a first length of a first material characterized by a first group index corresponding to a first phase delay to transfer a first light wave with a first peak frequency and a second arm comprising a second length of a second material characterized by a second group index corresponding to a second phase to transfer a second light wave with a second peak frequency with a time-delay difference relative to the first light wave. The first phase delay and the second phase delay are configured to change equally upon a change of temperature. The time-delay difference between the first light wave and the second light wave is set to be inversed value of a free spectral range (FSR) to align at least the first peak frequency to a channel of a designated frequency grid.

A 2-dimensional grating generates multi-mode light from two or more single-mode inputs. One or more waveguides couple the light from the single-mode inputs to the 2-dimensional grating. The 2-dimensional grating couples and transmits the generated multi-mode light to an optical fiber configured to support multiple modes.

A system is provided for training a device design network. The system includes an interface configured to input data of a device, a memory to store the device design network including an encoder, a decoder, and an adversarial block, and a processor. The processor is, in connection with the memory, configured to update the encoder and the decoder based on a first loss function to reduce the difference between the input data and output data of the decoder, wherein the encoder is constructed by at least one convolutional layer followed by at least one parallel fully connected layer to extract features of a layout of the device, and update the adversarial block to construct by maximizing a second loss function.

A device includes an optical splitter comprising a plurality of splitter outputs. The splitter outputs are out of phase and include a non-uniform phase front. The device includes a one-dimensional phase compensation array communicating with the optical splitter. The phase compensation array receives the non-uniform phase front and outputs a uniform phase front. The phase compensation array includes a plurality of array outputs. The device includes a tunable linear gradient phase shifter communicating with said phase compensation array to impart a linearly-varying phase shift across said plurality of array outputs, thereby steering a beam along a first angle in a first plane. The device includes a waveguide grating out-coupler communicating with said linear gradient phase shifter, and a uniform phase shifter communicating with the waveguide grating out-coupler. The uniform phase shifter steers the flat phase front along a second angle in a second plane perpendicular to said first plane.

Systems, methods, and techniques for optofluidic analyte detection and analysis using multi-mode interference (MMI) waveguides are disclosed herein. In some embodiments, spatially and spectrally multiplexed optical detection of particles is implemented on an optofluidic platform comprising multiple analyte channels intersecting a single MMI waveguide. In some embodiments, multi-stage photonic structures including a first stage MMI waveguide for demultiplexing optical signals by spatially separating different wavelengths of light from one another may be implemented. In some embodiments, a second stage may use single-mode waveguides and/or MMI waveguides to create multi-spot patterns using the demultiplexed, spatially separated light output from the first stage. In some embodiments, liquid-core MMI (LC-MMI) waveguides that are tunable by replacing a liquid core, heating/cooling the liquid core, and/or deforming the LC-MMI to change its width may be implemented in one or more of the analyte detection/analysis systems disclosed herein.

An integrated mode converter and multiplexer (/demultiplexer) is disclosed, which combines a multimode interference coupler (100), at least one phase-shifter (200) and a symmetrical Y-junction (300). The dispersion of the multimode interference coupler (100) is engineered through subwavelength structures in order to achieve a very wide bandwidth. Several phase-shifter (200) topologies for further bandwidth enhancement are disclosed, as well as architectures for multiplexing a greater number of optical modes.