A wavelength checker includes an optical waveguide chip. A known arrayed-waveguide diffraction grating is formed on the optical waveguide chip. The wavelength checker includes a light conversion unit made of a conversion material that converts infrared light into visible light. The light conversion unit is arranged on an output side of a plurality of first output waveguides of the optical waveguide chip to be capable of receiving light emitted from the plurality of first output waveguides. The light conversion unit is formed on a side surface of a support facing an output end surface of the optical waveguide chip. The support is fixed to a main board.

An optical waveguide apparatus including a first dispersion unit and a separation unit. The first dispersion unit is connected to the separation unit, the first dispersion unit is configured to disperse a frequency component of at least one first optical signal, and the separation unit is configured to separate, into at least one second optical signal based on configuration information, the frequency component that is of the at least one first optical signal and that is dispersed by the first dispersion unit. The separation unit is implemented by a variable optical waveguide, and the variable optical waveguide is an optical waveguide that implements at least one of the following functions based on the configuration information: forming an optical waveguide, eliminating an optical waveguide, and changing a shape of an optical waveguide.

One example optical splitter chip includes a substrate. The substrate is configured with an input port, configured to receive first signal light, an uneven optical splitting unit, configured to split the first signal light into at least second signal light and third signal light, where optical power of the second signal light is different from optical power of the third signal light, a first output port, configured to output the second signal light, an even optical splitting unit group, including at least one even optical splitting unit, configured to split the third signal light into at least two channels of equal signal light, where optical power of the at least two channels of equal signal light is the same, and at least two second output ports, which are in a one-to-one correspondence with the at least two channels of equal signal light.

A multi-path interference filter. The multi-path interference filter includes a first port waveguide, a second port waveguide, and an optical structure connecting the first port waveguide and the second port waveguide. The optical structure has a first optical path from the first port waveguide to the second port waveguide, and a second optical path, different from the first optical path, from the first port waveguide to the second port waveguide. The first optical path has a portion, having a first length, within hydrogenated amorphous silicon. The second optical path has a portion, having a second length, within crystalline silicon, and the second optical path has either no portion within hydrogenated amorphous silicon, or a portion, having a third length, within hydrogenated amorphous silicon, the third length being less than the first length.

A compact collimator or projector includes a waveguide having a slab core structure supporting at least two lateral modes of propagation. A light beam coupled into a first mode propagates to an edge of the waveguide where it is reflected by a reflector to propagate back. Upon propagation back and forth, the light is converted into a second mode. An out-coupling region, such as an evanescent coupler, is provided to out-couple the light propagating in the second mode. The reflector may have focusing power to collimate the out-coupled light beam. The light beam may be converted from the first to the second mode without being reflected from a reflector.

Structures for an optical power splitter and methods of forming a structure for an optical power splitter. A first waveguide core includes a portion positioned over a multimode interference region, a second waveguide core includes a portion positioned over the multimode interference region, and a third waveguide core includes a portion positioned over the multimode interference region. The first waveguide core provides an input port to the optical power splitter. The second waveguide core provides a first output port from the optical power splitter, and the third waveguide core provides a second output port from the optical power splitter.

Accelerating photonic and opto-electronic technologies requires breaking current limits of modern chip-scale photonic devices. While electronics and computer technologies have benefited from “Moore's Law” scaling, photonic technologies are conventionally limited in scale by the wavelength of light. Recent sub-wavelength optical devices use nanostructures and plasmonic devices but still face fundamental performance limitations arising from metal-induced optical losses and resonance-induced narrow optical bandwidths. The present disclosure instead confines and guides light at deeply sub-wavelength dimensions while preserving low-loss and broadband operation. The wave nature of light is used while employing metal-free (all-dielectric) nanostructure geometries which effectively “pinch” light into ultra-small active volumes, for potentially about 100-1000× reduction in energy consumption of active photonic components such as phase-shifters. The present disclosure could make possible all-optical and quantum computing devices which require extreme optical confinement to achieve efficient light-matter interactions.

Embodiments include a photonic device with a compensation structure. The photonic device includes a waveguide with a refractive index which changes according to the thermo-optic effect as a temperature of the photonic device fluctuates. The compensation structure is positioned on the photonic device to counteract or otherwise alter the thermo-optic effect on the refractive index of the waveguide in order to prevent malfunctions of the photonic device.

The present disclosure relates to thermal control systems, photonic memory fabrics, and electro-absorption modulators (EAMs). For example, the thermal control systems efficiently move data in a memory fabric based on utilizing and controlling thermally controlling optical components. As another example, the EAMs are instances of optical modulators used to efficiently move data within digital circuits while maintaining thermally-stable optical modulation across a wide temperature range.

A splitter. In some embodiments, the splitter includes an input waveguide; a first output waveguide; a second output waveguide; a first internal waveguide, connected to the input waveguide and to the first output waveguide, and a second internal waveguide, coupled to the first internal waveguide and connected to the second output waveguide. The splitter may be configured, when fed, at the input waveguide, power in a fundamental mode of the input waveguide or power in a first order spatial mode of the input waveguide: to transmit at least 80% of the power in the fundamental mode to the first output waveguide, and to transmit at least 80% of the power in the first order spatial mode to the second output waveguide.