A magnetic field sensor comprises a magnetically responsive light propagating component configured to cause a polarization of light propagating inside the component to be rotated in response to an applied magnetic field, wherein the magnetically responsive light propagating component is formed of a bulk material doped with a dopant, the dopant including at least gadolinium, the dopant concentration being at a sufficiently low concentration such that the dopant is uniformly dispersed in the bulk material to provide a high Verdet constant. The magnetic field sensor also comprises a detector, and a polarization-maintaining light input device to couple the light into the magnetically responsive light propagating component. The detector is configured to measure a property of light output from the magnetically responsive light propagating component to determine a change in polarization of the light, the change caused by the presence of a magnetic field.

Nonreciprocal optical transmission devices and optical apparatuses including the nonreciprocal optical transmission devices are provided. A nonreciprocal optical transmission device includes an optical input portion, an optical output portion, and an intermediate connecting portion interposed between the optical input portion and the optical output portion, and comprising optical waveguides. A complex refractive index of any one or any combination of the optical waveguides changes between the optical input portion and the optical output portion, and a transmission direction of light through the nonreciprocal optical transmission device is controlled by a change in the complex refractive index.

The invention relates to optical waveguide components, such as Faraday rotators and their manufacture Faraday rotators based on silicon waveguides are provided, where the waveguide has folded or wound sections that are parallel to an externally applied magnetic field.

The invention relates to optical waveguide components, such as Faraday rotators and their manufacture Faraday rotators based on silicon waveguides are provided, where the waveguide has folded or wound sections that are parallel to an externally applied magnetic field.

Nonreciprocal optical transmission devices and optical apparatuses including the nonreciprocal optical transmission devices are provided. A nonreciprocal optical transmission device includes an optical input portion, an optical output portion, and an intermediate connecting portion interposed between the optical input portion and the optical output portion, and comprising optical waveguides. A complex refractive index of any one or any combination of the optical waveguides changes between the optical input portion and the optical output portion, and a transmission direction of light through the nonreciprocal optical transmission device is controlled by a change in the complex refractive index.

A Faraday rotator and an optical isolator having a high transmittance and a high Verdet constant are provided. The optical isolator includes at least a Faraday rotator that rotates a polarization plane of incident light in a non-reciprocal manner, a polarizer disposed on a light incident side of the Faraday rotator, and an analyzer disposed on a light exit side of the Faraday rotator. The Faraday rotator is made of an oxide containing ytterbium oxide (Yb.sub.2O.sub.3), and is manufactured by a ceramic manufacturing process, wherein the oxide is allowed to contain an oxide of a metal other than ytterbium, and the proportion of ytterbium in all metal atoms in the oxide is 80% or more.

Provided a two-dimensional photonic crystal device in which are inserted three waveguides and one resonant cavity by the creation of linear and local defects. Due to the photonic band gap related to the photonic crystal, electromagnetic signals are confined to the interior of waveguides and resonant cavity. By exciting dipole modes in the resonant cavity, with orientation that depends on the intensity of the applied DC magnetic field, the present circulator device can provide the nonreciprocal transmission of signals in the clockwise and counterclockwise directions. It can fulfill the isolation function and it is fork-shaped, providing greater flexibility in the design of integrated optical communication systems.

An optoelectronic system includes a concentration layer, a modulation layer including an array of light modulators, an exit layer that receives the modulation layer output having a modulation layer output spatial distribution and remaps the modulation layer output spatial distribution to a modified spatial distribution. A collector layer receives the modified spatial distribution to produce a collector layer output. A detector receives the collector layer output. A processor controls the modulation layer and receives the detector output to generate an image. The collector layer can receive the modified spatial distribution at a plurality of collector layer inputs and combine the plurality of collector layer inputs at a collector layer output. Modulators can be configured to direct couple modulated light to a collector layer, without using an exit layer. Configurations with spatial light modulator modules and sub-modules are described.

An optoelectronic system includes a concentration layer, a modulation layer including an array of light modulators, an exit layer that receives the modulation layer output having a modulation layer output spatial distribution and remaps the modulation layer output spatial distribution to a modified spatial distribution. A collector layer receives the modified spatial distribution to produce a collector layer output. A detector receives the collector layer output. A processor controls the modulation layer and receives the detector output to generate an image. The collector layer can receive the modified spatial distribution at a plurality of collector layer inputs and combine the plurality of collector layer inputs at a collector layer output. Modulators can be configured to direct couple modulated light to a collector layer, without using an exit layer. Configurations with spatial light modulator modules and sub-modules are described.

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.