The disclosure relates in some aspects to providing miniature power-efficient agile photonic generators of microwave waveforms. Illustrative examples use chip lasers integrated in close thermal proximity with one another to provide a miniature microwave arbitrary waveform generator (AWG). Due to the small size of the lasers and the close integration, common ambient fluctuations from the environment or other sources can be efficiently reduced, yielding improved spectral purity of generated radio-frequency (RF) signals. Tight physical integration also permits a small device footprint with minimal acceleration sensitivity. The lasers may be locked to cavities or other resonators to allow efficient decoupling of the frequency and amplitude modulation of the lasers to provide flexibility to the waveform generator. Exemplary devices described herein can produce frequency chirped signals for radar applications. The frequency chirp may be linear and/or nonlinear. Tuning methods are also described herein.

Apparatus and methods for altering one or more spectral, spatial, or temporal characteristics of a light-emitting device are disclosed. Generally, such apparatus may include a volume Bragg grating (VBG) element that receives input light generated by a light-emitting device, conditions one or more characteristics of the input light, and causes the light-emitting device to generate light having the one or more characteristics of the conditioned light.

A laser source is presented a plurality of unit cells of a selected number of partially physically coupled lasing units arranged within a plane and configured to form a topological structure, wherein each of the lasing units is configured to emit radiation component substantially perpendicular to said plane, said plurality of the unit cells comprising at least a first sub-array of the unit cells located in a first region interfacing with a second region of a different type than said first region, thereby defining an arrangement of optically coupled lasing units along an interface region between the first and second adjacent regions, forming at least one topological state along a topological path within said interface region.

In various embodiments, laser systems or resonators incorporate two separate cooling loops that may be operated at different cooling temperatures. One cooling loop, which may be operated at a lower temperature, cools beam emitters. The other cooling loop, which may be operated at a higher temperature, cools other mechanical and/or optical components, for example optical elements such as lenses and/or reflectors.

In various embodiments, one or more optical elements are utilized to alter the numerical aperture of a radiation beam received from an optical fiber in order to accommodate the properties of a downstream collimator within a laser delivery head.

A device, such as a light-emitting device, e.g. a laser device, comprising: a plurality of group III-V semiconductor NWs grown on one side of a graphitic substrate, preferably through the holes of an optional hole-patterned mask on said graphitic substrate; a first distributed Bragg reflector or metal mirror positioned substantially parallel to said graphitic substrate and positioned on the opposite side of said graphitic substrate to said NWs; optionally a second distributed Bragg reflector or metal mirror in contact with the top of at least a portion of said NWs; and wherein said NWs comprise aim-type doped region and a p-type doped region and optionally an intrinsic region there between.

There is provided a device to generate an output light. The device comprises a substrate, a quantum well structure (QWS) disposed on the substrate, and a waveguide disposed on the substrate and in contact with the QWS. The QWS has a first layer, a second layer, and a third layer. The second layer is disposed and quantum-confined between the first layer and the third layer. In addition, the second layer is to emit an input light when electrically biased. The input light has an optical field extending outside the QWS and into the waveguide, to optically couple the waveguide with the QWS. The waveguide is to provide an optical resonance cavity for the input light. Moreover, the waveguide has an optical outlet to transmit at least some of the input light out of the waveguide to generate the output light.

A plasmonic laser array device may comprise a first microcavity element having a first radiating end facet and a second radiating end facet opposite the first radiating end facet in a longitudinal direction of the device. The device may comprise a second microcavity element having a third radiating end facet and a fourth radiating end facet opposite the third radiating facet in the longitudinal direction. The device may comprise a first microcavity gap configured to separate the first microcavity element and the second microcavity element in the longitudinal direction. The device may comprise a bottom (e.g., metal) layer configured to underly the first microcavity element, the second microcavity element, and the first microcavity gap. The device may comprise an arrangement that places the first microcavity element and the second microcavity element into a phase-locked orientation for a phased-locked operation of the plasmonic laser array device.

In various embodiments, laser systems or resonators incorporate two separate cooling loops that may be operated at different cooling temperatures. One cooling loop, which may be operated at a lower temperature, cools beam emitters. The other cooling loop, which may be operated at a higher temperature, cools other mechanical and/or optical components, for example optical elements such as lenses and/or reflectors.

It is an aim of the present invention to provide ultra-compact highly-integrated diffraction-grating semiconductor lasers on chips. Various embodiments combined enable the lasers to be compact in size, light weight, mechanically rugged, low in manufacturing cost, and in some cases high in electrical wall-plugged power efficiency or high in optical power output, comparing to typical lasers based on discrete optical components.