A semiconductor laser diode is disclosed. In an embodiment a semiconductor laser diode includes a first resonator and a second resonator, the first and second resonators having parallel resonator directions along a longitudinal direction and being monolithically integrated into the semiconductor laser diode, wherein the first resonator includes at least a part of a semiconductor layer sequence having an active layer and an active region configured to be electrically pumped to generate a first light, wherein the longitudinal direction is parallel to a main extension plane of the active layer, and wherein the second resonator has an active region with a laser-active material configured to be optically pumped by at least a part of the first light to produce a second light which is partially emitted outwards from the second resonator.

A system includes a master oscillator configured to generate a low-power optical beam. The system also includes a planar waveguide (PWG) amplifier configured to receive the low-power optical beam and generate a high-power optical beam having a power of at least about ten kilowatts. The PWG amplifier includes a single laser gain medium configured to generate the high-power optical beam. The single laser gain medium can reside within a single amplifier beamline of the system. The master oscillator and the PWG amplifier can be coupled to an optical bench assembly, and the optical bench assembly can include optics configured to route the low-power optical beam to the PWG amplifier and to route the high-power optical beam from the PWG amplifier. The PWG amplifier could include a cartridge that contains the single laser gain medium and a pumphead housing that retains the cartridge.

A laser source includes a topological cavity for nonreciprocal lasing, a magnetic material and an optical waveguide. The magnetic material is arranged to interact with the topological cavity. The optical waveguide is arranged to receive light extracted from the topological cavity upon breaking of time-reversal symmetry in the topological cavity.

A laser source includes a topological cavity for nonreciprocal lasing, a magnetic material and an optical waveguide. The magnetic material is arranged to interact with the topological cavity. The optical waveguide is arranged to receive light extracted from the topological cavity upon breaking of time-reversal symmetry in the topological cavity.

Core-cladding planar waveguide (PWG) structures and methods of making and using same. The core-cladding PWG structures can be synthesized by hydride vapor phase epitaxy and processed by mechanical and chemical-mechanical polishing. An Er doping concentration of [Er] between 1×10.sup.18 atoms/cm.sup.3 and 1×10.sup.22 atoms/cm.sup.3 can be in the core layer. Such PWGs have a core region that can achieve optical confinement between 96% and 99% and above.

A laser is disclosed having a housing formed of a block of glass-ceramic. The block is machined (or otherwise formed) to define one or more channels that act as a waveguide in two dimensions for light within the laser resonator. The channels extend between cavities also formed within the block which retain optical components of the laser, e.g. one or more of the gain medium, cavity mirrors, intermediate reflectors etc. The positioning, shape and size of each cavity is bespoke for the optical component it holds in order that each optical component is retained in optical alignment rigidly against the sides of the cavity.

A ring optical resonator and one or more input optical waveguides are arranged on a substrate, and are arranged and positioned to establish evanescent optical coupling between them. The ring optical resonator, the substrate, or both include one or more nonlinear optical materials. To detect an electromagnetic signal at frequency ν.sub.EM incident on the resonator, an input optical signal at frequency ν.sub.IN propagates along the waveguide and around the resonator. The incident electromagnetic signal and the input optical signal generate one or more sideband optical signals at corresponding optical sideband frequencies ν.sub.SF=ν.sub.IN+ν.sub.EM or ν.sub.DF=ν.sub.IN−ν.sub.EM. To generate an electromagnetic signal to propagate away from the resonator, input optical signals at frequencies ν.sub.IN1 and ν.sub.IN2 propagate along one or more waveguides and around the resonator and generate the electromagnetic signal incident at frequency ν.sub.EM=|ν.sub.IN1−ν.sub.IN2|.

An optical element includes an optical material including a first edge and an opposing second edge. The optical element further includes a plurality of micro-channels arranged within the optical material. Each of the micro-channels of the plurality of micro-channels extends from the first edge to the second edge of the optical material.

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.

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.