A broadband optical wavelength multiplexer/demultiplexer is provided. Two waveguides are arranged such that, in a case where a connection position where one of the two waveguides is connected to a first slab waveguide is set closer to the other waveguide by a channel frequency interval f, a central position between the two waveguides aligns with a central position on a connection end surface of the first slab waveguide, and two waveguide groups of an output waveguide are arranged such that a central position between the two waveguide groups aligns with a central position of a second slab waveguide, and an interval between a connection position where the other waveguide is connected to the first slab waveguide and the central position on the connection end surface of the first slab waveguide is set equal to an interval between a connection position where the waveguide groups are connected to the second slab waveguide.

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 single mode waveguide with a straight portion and a curved portion, the curved portion having the shape of an adiabatic bend. The single mode waveguide has a curved portion that is shaped according to an adiabatic bend, with a curvature that varies continuously, and that vanishes at a point at which the curved portion is contiguous with a straight portion of the waveguide. The absence of curvature discontinuities avoids the coupling, within the waveguide, of optical power from a fundamental mode into a higher order mode and the curvature of the curved portion results in attenuation of optical power, in higher order modes, that may be coupled into the waveguide at either end.

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.

A leaky waveguide includes a waveguide configured to propagate light; a defect structure provided on a portion of the waveguide and configured to cause the light propagating in the waveguide to leak outside of the waveguide; and a plurality of detectors provided at predetermined positions adjacent to the defect structure and configured to detect the light leaking from the defect structure. Accordingly, a spectroscope including the leaky waveguide may have a reduced size.

A light splitting device includes an optical waveguide body and a dispersion grating. The optical waveguide body is configured to transmit incident light to the dispersion grating, the dispersion grating is configured to disperse the incident light transmitted by the optical waveguide body into a plurality of spectral lines, and the optical waveguide body is further configured to change propagation directions of the plurality of spectral lines and to emit the plurality of spectral lines.

An optical circuit includes an input waveguide, an arrayed waveguide including a plurality of output waveguides, a coupler, an electrode capable of applying a voltage to each of the output waveguides of the arrayed waveguide, and a chip unit to which the input waveguide, the coupler, and a portion of the arrayed waveguide are fixed. The arrayed waveguide is divided into a phase shifter portion capable of generating a predetermined phase difference between adjacent ones of the output waveguides, a beam portion having a cantilever structure that is not fixed by the chip unit, and a waveguide portion between the phase shifter portion and the beam portion. The electrode is capable of applying positive and negative voltages to the beam portion of the arrayed waveguide such that positive and negative voltages are alternately applied to adjacent ones of the output waveguides.

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.

One example optical splitter chip includes a substrate, where 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.

In one example, a chip-scale emitter includes a resonator formed in a waveguide, wherein the resonator includes a first grating formed in the waveguide and a second grating formed in the waveguide that is separate from the first grating; and a scattering element consisting of a single defect in the waveguide, wherein the scattering element is positioned between the first grating and the second grating in the waveguide.