A semiconductor-fiber-laser assembly is provided that includes a pumping module, an active optical fiber and an assembling board. The active optical fiber is provided on an upper surface of the assembling board, the pumping module is provided on a surface of the assembling board that is the same as or opposite to the upper surface; and input-side and output-side optical-fiber gratings are provided at two ends of the active optical fiber, to form a laser resonator between the input-side and output-side optical-fiber gratings. The pumping module includes a plurality of semiconductor-laser single emitters, a collimating-lens group and a mirror group that are sequentially arranged, and light beams from the semiconductor-laser single emitters pass through the mirror group to realize beam combination.

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.

A security or identification device comprises a membrane laser structure configured to be optically pumped. The membrane laser structure comprises a flexible emission layer comprising a gain material; and one or more structures formed in or associated with the flexible emission layer and configured to provide optical feedback in the emission layer to produce a laser light output having at least one property representing an identifier.

A MEMS tunable VCSEL includes a membrane device having a mirror and a distal-side electrostatic cavity for displacing the mirror to increase a size of an optical cavity. A VCSEL device includes an active region for amplifying light. Then, a proximal-side electrostatic cavity is defined between the VCSEL device and the membrane device is used to displace the mirror to decrease a size of an optical cavity.

A topological bulk laser includes a topological photonic crystal (32) having an energy band inversion between dipole mode and quadrupole mode near the center of Brillouin zone and a trivial photonic crystal (31) not having band inversion for splicing to each other. The reflection and confinement of an optical field occurs at the interface; and the interface encloses to form a closed contour, thereby forming a laser cavity with an effective cavity feedback for lasing at the interior of the interface. This band-inversion-induced reflection mechanism induces single-mode lasing with directional vertical emission. At room temperature, the topological bulk laser can achieve low threshold, narrow linewidth, and a high side-mode suppression ratio, reduce the fabrication difficulty and costs, and improve heat dissipation and electrical injection efficiency, hence improving lifetime and stability of devices.

A collinear T-cavity VECSEL system generating intracavity Hermite-Gaussian modes at multiple wavelengths, configured to vary each of these wavelengths individually and independently. A mode converter element and/or an astigmatic mode converter is/are aligned intracavity to reversibly convert the Gaussian modes to HG modes to Laguerre-Gaussian modes, the latter forming the system output having any of the wavelengths provided by the spectrum resulting from nonlinear frequency-mixing intracavity (including generation of UV, visible, mid-IR light). The laser system delivers Watt-level output power in tunable high-order transverse mode distribution.

Disclosed here are methods, devices, and systems for generating an output light beam for a pulsed laser. An example method may comprise generating one or more pump optical beams comprising at least two photons having a pump wavelength. A first nonlinear stage may convert the at least two photons to a first photon having a first wavelength that is half of the pump wavelength. The first optical beam may be caused to spatially overlap with a seed optical beam. At least two second nonlinear stages separated by a gap may be used to convert, based on the seed optical beam, the first photon to a second photon having a second wavelength and a third photon having a target wavelength greater than the pump wavelength. A third nonlinear stage may convert the second photon to a fourth photon and a fifth photon each having the target wavelength or having a wavelength within an offset range of the target wavelength.

A visible light source includes a substrate, a vertical-cavity surface-emitting laser including an active semiconductor region configured to emit infrared light and a first reflector configured to reflect the infrared light emitted by the active semiconductor region, a second reflector configured to reflect the infrared light and form a vertical cavity for the infrared light with the first reflector, and one or more micro-resonators configured to receive the infrared light and generate visible light in one or more colors using the infrared light through optical parametric oscillation. The visible light source also includes one or more output couplers configured to couple the visible light in one or more colors from the one or more micro-resonators into free space or into a photonic integrated circuit.

A laser system produces pulses having wavelengths between 2000 nm and 2100 nm, peak output powers greater than 1 kW, average powers greater than 10 W, pulse widths variable from 0.5 to 10 nsec, pulse repetition frequencies variable from 0.1 to over 2 MHz, and a pulse extinction of at least 60 dB. Pulses from a diode laser having a wavelength between 1000 nm and 1100 nm are amplified by at least one fiberoptic amplifier and applied as the pump input to an Optical Parametric Amplifier (OPA). A cw laser provides an OPA seed input at a wavelength between 2000 nm and 2200 nm. The idler output of the OPA having difference frequency wavelength between 2000 nm and 2100 nm is further amplified by a crystal amplifier. The fiberoptic amplifier can include Ytterbium-doped fiberoptic. The crystal amplifier can include a Ho:YAG, Ho:YLF, Ho:LuAG, and/or a Ho:Lu2O3 crystal.

A narrow linewidth mid infrared laser, including a pumping laser diode with a fast-axis compressor and a pumping wavelength λ.sub.o; and an optical resonator arranged to receive the pumping wavelength λ.sub.o, the optical resonator including a laser crystal with a lasing wavelength λ.sub.p, a dichroic mirror, and a nonlinear crystal to generate an idler wavelength λ.sub.i.