An integrated photonic circulator is described, an application of which may be deployed on a chip-scale light-detection and ranging (LiDAR) device. The photonic circulator includes a micro-ring resonator waveguide, a heating element, first and second bus waveguides, a magneto-optic substrate, a magneto-optic element, a magnetic ring disposed on a photonic substrate, and a silicon substrate. The first and second bus waveguides are coupled to the micro-ring resonator waveguide, and the micro-ring resonator waveguide is affixed onto a first side of the photonic substrate. The magneto-optic element and the magneto-optic substrate are arranged on the micro-ring resonator waveguide, the magnetic ring is affixed to the magneto-optic substrate, the heating element is affixed to the photonic substrate, the photonic substrate is affixed to the silicon substrate, and the magnetic ring is concentric with the micro-ring resonator.

An architecture for a chip-scale optical phased array-based scanning frequency-modulated continuous wave (FMCW) Light-detection and ranging (LiDAR) device is described. The LiDAR device includes a laser, a transmit optical splitter, an optical circulator, photodetectors, and an optical phased array. The laser, the transmit optical splitter, the optical circulator, the photodetectors, and the optical phased array are arranged as a chip-scale package on a single semiconductor substrate. The laser generates a first light beam that is transmitted to the optical phased array aperture via the transmit optical splitter, the optical circulator, and the optical phased array. A fraction of the first light beam is transmitted to the photodetectors via the transmit optical splitter to serve as the optical local oscillator (LO), the aperture of the optical phased array captures a second light beam that is transmitted to the photodetectors via the optical phased array and the optical circulator.

An apparatus including a light detection and ranging (LiDAR) antenna of an optical phased array includes a silicon-on-insulator substrate including a silicon wire waveguide embedded within the substrate and a grating layer disposed over the substrate. The grating layer includes a silicon nitride layer coating the silicon-on-insulator substrate and including a plurality of etchings formed in a direction perpendicular to a longitudinal axis of the optical phased array and a silicon oxynitride layer coating the silicon nitride layer and filling the etchings. The etchings are relatively thin in the direction of the longitudinal axis of the optical phased array at a first end of the optical antenna and are relatively thick in the direction of the longitudinal axis at a second end. The etchings gradually increase in thickness between the first end of the optical phased array and the second end of the optical antenna.

A spatial light modulator system includes a concentration layer including an array of optical concentrators, such that each concentrator concentrates a portion of an input light beam. A modulation layer includes an array of light modulators each in optical communication with one of the optical concentrators for modulating the portion of the input light beam. The light modulators are spaced apart from one another in the modulation layer to form gaps between adjacent ones of the light modulators. A coil of each light modulator can surround a Faraday element or core containing a Faraday material to control a magnetic state of a Faraday material responsive to control signals.

A spatial light modulator system includes a concentration layer including an array of optical concentrators, such that each concentrator concentrates a portion of an input light beam. A modulation layer includes an array of light modulators each in optical communication with one of the optical concentrators for modulating the portion of the input light beam. The light modulators are spaced apart from one another in the modulation layer to form gaps between adjacent ones of the light modulators. A coil of each light modulator can surround a Faraday element or core containing a Faraday material to control a magnetic state of a Faraday material responsive to control signals.

An isolator includes a first core, a second core, a nonreciprocal member, and a magnetic body. The first core and the second core extend in a first direction and are positioned side by side with a cladding therebetween in a second direction that intersects the first direction. The nonreciprocal member is in contact with at least a part of the second core while being positioned side by side with the second core in the second direction. In a magnetic field generated by the magnetic body in a portion where the nonreciprocal member is positioned, a component in a third direction perpendicular to the first direction and the second direction is greater than any component other than the component in the third direction.

An optical isolator on a silicon photonic integrated circuit. The optical isolator comprising: a polarization splitter; a polarization rotator; and a Faraday rotator. The Faraday rotator comprises: one or more magnets providing a magnetic field; and a silicon spiral delay line. The silicon spiral delay line being formed from a silicon waveguide shaped into a spiral region having no built-in phase shifters and a central region within the spiral region. The central region having no more than a total of 180 degree of phase shifters.

A method of fabricating a gyrotropic device (e.g., an optical isolator) includes: providing a substrate comprising a waveguide layer and forming an optical isolator active layer on the waveguide layer of the substrate. Forming the optical isolator active layer includes, for a specified composition of the optical isolator active layer, deriving at least one sputtering process parameter, performing sputtering of a plurality of targets according to the at least one sputtering process parameter to deposit the optical isolator active layer on the waveguide layer of the substrate, measuring an initial value of a bias voltage at a first target of the plurality of targets; and throughout deposition of the optical isolator active layer, maintaining the bias voltage at the initial value to within a predetermined threshold of the initial value.

A spatial light modulator system includes a concentration layer including an array of optical concentrators, such that each concentrator concentrates a portion of an input light beam. A modulation layer includes an array of light modulators each in optical communication with one of the optical concentrators for modulating the portion of the input light beam. The light modulators are spaced apart from one another in the modulation layer to form gaps between adjacent ones of the light modulators. A coil of each light modulator can surround a Faraday element or core containing a Faraday material to control a magnetic state of a Faraday material responsive to control signals.

A spatial light modulator system includes a concentration layer including an array of optical concentrators, such that each concentrator concentrates a portion of an input light beam. A modulation layer includes an array of light modulators each in optical communication with one of the optical concentrators for modulating the portion of the input light beam. The light modulators are spaced apart from one another in the modulation layer to form gaps between adjacent ones of the light modulators. A coil of each light modulator can surround a Faraday element or core containing a Faraday material to control a magnetic state of a Faraday material responsive to control signals.