A grating emitter method and system for modulating the polarization of an optical beam, such as one for transmission through free-space or use in an atomic clock.

An optical circulator is a device that routes optical pulses from port to port in a predetermined manner, e.g. in a 3-port optical circulator, optical pulses entering port 1 are routed out of port 2, while optical pulses entering port 2 exit out of port 3 and optical pulses fed into port 3 exit out of port 3. Currently such an optical circulator is made of discrete components such as magnetooptic garnets, rare-earth magnets and optical polarizers that are packaged together with fiber optic elements. Disclosed herein is a different kind of optical circulator that is monolithically integrated on a single semiconductor substrate and that is applicable for the routing of optical pulses. The embodied invention will enable photonic integrated circuits to incorporate on-chip optical circulator functionality thereby allowing much more complex optical designs to be implemented monolithically.

A monolithically integrated optical device. The device has a gallium and nitrogen containing substrate member having a surface region configured on either a non-polar or semi-polar orientation. The device also has a first waveguide structure configured in a first direction overlying a first portion of the surface region. The device also has a second waveguide structure integrally configured with the first waveguide structure. The first direction is substantially perpendicular to the second direction.

Structures for response shaping in frequency and time domain, include an optical response shaper and/or a modulator device with multiple injection. The device comprises a resonator having an enclosed geometric structure, for example a ring or racetrack structure, at least two injecting optical waveguides approaching the resonator to define at least two coupling regions between the resonator and the injecting waveguides, and may define at least two Free Spectral Range states. One or both of the coupling regions has a coupling coefficient selected for a predetermined frequency or time response, and the coupling coefficient or other device parameters may be variable, in some case in real time to render the response programmably variable.

A laser comprising: at least one wavelength selective reflector that comprises a waveguide vertically coupled to at least one photonic crystal resonator, the waveguide and photonic crystal resonator being arranged to provide wave-vector matching between at least one mode of the photonic crystal resonator and at least one mode of the waveguide; an optical gain medium for generating light for coupling into the waveguide, and a reflector at an end of the optical gain medium, the reflector and the photonic crystal resonator defining a laser cavity. Light generated by the optical gain medium is coupled into the waveguide and coupled into the photonic crystal resonator, and partially reflected back to the optical gain medium.

The present invention discloses a semiconductor laser comprising an optical waveguide structure which may include a lower waveguide layer, an active layer of multiple quantum wells and an upper waveguide layer, which are successively stacked from bottom to top, a grating layer being formed on upper portion of the active layer, wherein the upper waveguide layer, a cladding layer and a contact layer are formed as a ridge which has a light incidence end surface and a light output end surface, wherein a beam expanding structure is formed on one end of the output end surface. The beam expanding structure has a beam expanding portion with a shape gradually contracted inwards from the light output end surface. Preferably, the beam expanding portion has a horizontal divergence angle of 5° to 20°.

A semiconductor laser includes a semiconductor layer including end faces and at least one of the end faces is configured as a light emission end face. The semiconductor layer includes a waveguide and a light window structure region. The waveguide has a first width and is extended between the end faces. The light window structure region includes an opening having a second width greater than the first width arranged along the waveguide and is formed continuously or intermittently from one to another of the end faces.

The invention relates to laser diode for generating laser radiation of at least two frequencies, comprising: a semiconductor body having a ridge waveguide; a DFB structure or DBR structure in the ridge waveguide; and a piezoelectric element for producing mechanical stress in the ridge waveguide, which piezoelectric element is arranged on the ridge waveguide. The invention further relates to a method for producing laser radiation of at least two frequencies by means of the laser diode.

A reflector structure for a tunable laser and a tunable laser. A super structure grating is used as a reflector structure, and a suspended structure is formed around a region in which the super structure grating is located, to implement, using the suspended structure, thermal isolation around the region in which the super structure grating is located, and increase thermal resistance, such that less heat is lost, and heat is concentrated in the region in which the super structure grating is located, thereby improving thermal tuning efficiency of the reflector structure. Moreover, lateral support structures are disposed on two sides of the suspended structure, to provide a mechanical support for the suspended structure. In addition, regions in the super structure grating that correspond to any two lateral support structures on a same side of the suspended structure fall at different locations in a spatial period of the super structure grating.

A monolithically integrated optical device. The device has a gallium and nitrogen containing substrate member having a surface region configured on either a non-polar or semi-polar orientation. The device also has a first waveguide structure configured in a first direction overlying a first portion of the surface region. The device also has a second waveguide structure integrally configured with the first waveguide structure. The first direction is substantially perpendicular to the second direction.