High-power, phased-locked, laser arrays as disclosed herein utilize a system of optical elements that may be external to the laser oscillator array. Such an external optical system may achieve mutually coherent operation of all the emitters in a laser array, and coherent combination of the output of all the lasers in the array into a single beam. Such an “external gain harness” system may include: an optical lens/mirror system that mixes the output of all the emitters in the array; a holographic optical element that combines the output of all the lasers in the array, and an output coupler that selects a single path for the combined output and also selects a common operating frequency for all the coupled gain regions.

High-power, phased-locked, laser arrays as disclosed herein utilize a system of optical elements that may be external to the laser oscillator array. Such an external optical system may achieve mutually coherent operation of all the emitters in a laser array, and coherent combination of the output of all the lasers in the array into a single beam. Such an “external gain harness” system may include: an optical lens/mirror system that mixes the output of all the emitters in the array; a holographic optical element that combines the output of all the lasers in the array, and an output coupler that selects a single path for the combined output and also selects a common operating frequency for all the coupled gain regions.

A semiconductor laser diode includes a semiconductor body having an emitter region; and a first connection element that electrically contacts the semiconductor body in the emitter region, wherein the semiconductor body is in contact with the first connection element in the emitter region, and at least in places in the emitter region, the semiconductor body has a structuring that enlarges a contact area between the semiconductor body and the first connection element.

A method for manufacturing a light emitting device can include providing a substrate; forming a first active layer with a first electrical polarity; forming a light emitting region configured to emit light with a target wavelength between 200 nm and 300 nm; forming a second active layer with a second electrical polarity; forming a first electrical contact layer, optionally comprising a first optical reflector; removing a portion of the first electrical contact layer, the second active layer, the light emitting region, and the first active layer to form a plurality of mesas; and forming a second electrical contact layer. Each mesa can include a mesa width smaller than 10 times the target wavelength that confines the emitted light from the light emitting region to fewer than 10 transverse modes, or a mesa width smaller than twice a current spreading length of the light emitting device.

A vertical external cavity surface emitting laser (VECSEL) based system in a linear single cavity configuration is configured to deliver light in higher-order Hermite-Gaussian transverse modes with Watt-level output power. Simultaneous and independent lasing of spatially-restructurable multiple high-order transverse modes that are collinearly-propagating at the output of such laser cavity is facilitated with the use of an optical pumping scheme devised to control positions of location at which the gain medium of the system is pumped (e.g., locations of focal spots of multiple pump beams on the gain-medium chip). An external astigmatic mode converter is utilized to convert such high-order Hermite-Gaussian modes into corresponding Laguerre-Gaussian modes.

Laser Side Mode Suppression Ratio (SMSR) control is provided via a logic controller configured to measure an SMSR of a carrier wave upstream of a modulator and measure an Average Optical Power (AOP) of the carrier wave downstream of the modulator; transmit a bias voltage based on the SMSR and the AOP to a laser driver for a laser generating the carrier wave; and transmit an attenuation level based on the SMSR and the AOP to a Variable Optical Attenuator (VOA) upstream of the modulator. In various embodiments the attenuation level and bias voltage can rise or fall together, or one may rise and one may fall to ensure the output optical signal meets specified SMSR and AOP values.

A beam combining device and method for a Bragg grating external-cavity laser module has a plurality of side by side light-emitting modules that use a Bragg grating to perform wavelength locking. Output light of the modules is incident to a beam combining element after passing through a focusing optical element for beam combining, and light subjected to beam combining is reflected partially and transmitted partially under the effect of a light splitting element. A part is incident into a dispersion element at a diffraction angle of the element. Parallel light is formed under the effect of a conversion optical element. Spots of the light beams of corresponding wavelengths of the light-emitting modules are formed on an image acquisition mechanism. Whether the wavelengths of the corresponding light-emitting modules are locked is determined by whether there is a deviation between preset spots and spots formed by the module on the acquisition mechanism.

A non-reciprocal optical assembly for injection locking a laser to a resonator is described. The laser emits a light beam, and the resonator receives the light beam and returns a feedback light beam to the laser such that the feedback light beam causes injection locking. The non-reciprocal optical assembly is interposed between and optically coupled to the laser and the resonator. The non-reciprocal optical assembly includes a first port that receives the light beam from the laser, and a second port that outputs the light beam to the resonator and receives the feedback light beam from the resonator. The first port also outputs the feedback light beam to the laser. The light beam passes through the non-reciprocal optical assembly with a first power loss, and the feedback light beam passes through the non-reciprocal optical assembly with a second power loss (the first power loss differs from the second power loss).

An optical source is described. This optical source includes a semiconductor optical amplifier (with a semiconductor other than silicon) that provides an optical gain medium and that includes a reflector. Moreover the hybrid external cavity laser includes a photonic chip with: an optical waveguide that conveys an optical signal output by the semiconductor optical amplifier; and a ring resonator, having a resonance wavelength, which reflects at least a resonance wavelength in the optical signal, where the reflector and the ring resonator define an optical cavity. Furthermore, the photonic chip includes: a thermal-tuning mechanism that adjusts the resonance wavelength; a photo-detector that measures an optical power output by the ring resonator; and control logic that adjusts the temperature of the ring resonator based on the measured optical power to lock a cavity mode of the optical cavity to a carrier wavelength.

An optical source is described. This optical source includes a semiconductor optical amplifier (with a semiconductor other than silicon) that provides an optical gain medium and that includes a reflector. Moreover the hybrid external cavity laser includes a photonic chip with: an optical waveguide that conveys an optical signal output by the semiconductor optical amplifier; and a ring resonator, having a resonance wavelength, which reflects at least a resonance wavelength in the optical signal, where the reflector and the ring resonator define an optical cavity. Furthermore, the photonic chip includes: a thermal-tuning mechanism that adjusts the resonance wavelength; a photo-detector that measures an optical power output by the ring resonator; and control logic that adjusts the temperature of the ring resonator based on the measured optical power to lock a cavity mode of the optical cavity to a carrier wavelength.