An arrangement for generating amplified spontaneous emission (ASE) over the combination of the C-band and L-band wavelength ranges is proposed, based on a reflective topology that reduces the number of individual components (compared with separate C-band and L-band ASE sources) required to generate the broadband ASE output. A pair of ASE generators are used, where at least one of the generators is configured to include a reflective element at a termination of the included gain fiber. The inclusion of the reflective element allows for the generated emission to pass through the gain fiber twice (emulating the operation of a conventional dual-stage ASE source). A long wavelength portion of the ASE created by a first ASE generator may be used as a seed input by the remaining ASE generator of the pair to further increase the efficiency of extending the ASE along the L-band wavelength range.

Mid-Wave Infrared (MWIR) laser systems emits at multiple wavelengths spanning the mid-IR transmission bands with tunability not to coincide with absorption lines within the bands. Optical fiber-based pump sources and a series of Raman fiber wavelength shifting amplifiers create a single output aperture that contains multiple spectral lines within each MWIR sub-band.

A movable diffraction grating includes: a support portion; a movable portion swingably connected to the support portion; a coil buried in the movable portion; a magnetic field generator configured to apply a magnetic field to the coil; an insulation layer provided on a surface of the movable portion; a resin layer provided on the insulation layer and provided with a diffraction grating pattern; and a reflection layer formed of a metal and provided on the resin layer to follow the diffraction grating pattern.

An Nd.sup.3+ optical fiber laser and amplifier operating in the wavelength range from 1300 to 1450 nm is described. The fiber includes a rare earth doped optical amplifier or laser operating within this wavelength band is based upon an optical fiber that guides light in this wavelength band. The waveguide structure attenuates light in the wavelength range from 850 nm to 950 nm and from 1050 nm to 1150 nm.

Multilayer structures containing porosified or electropolished layers of indium phosphide or gallium arsenide are described. Further disclosed are methods for preparing and using such multilayer structures, for example, in vertical cavity surface emitting lasers (VCSELs).

A single arm laser system comprising a first in-phase quadrature modulator, IQM. The first IQM is configured to receive a single frequency fibred laser beam from a frequency locked laser seed, generate a first single side-band frequency based on a carrier frequency of the single frequency fibred laser beam and suppress the carrier frequency, and output a first fibre laser beam having a single side-band suppressed carrier frequency. The single arm laser system also comprises a second IQM in line with the first IQM. The second IQM is configured to receive the first fibre laser beam from the first IQM, generate a second single side-band frequency based on the first single side-band frequency and maintain the first single side-band frequency as the carrier frequency, and output a second fibre laser beam having the first and second single side band frequencies.

A method for fabricating a laser diode device includes providing a gallium and nitrogen containing substrate member comprising a surface region, a release material overlying the surface region, an n-type gallium and nitrogen containing material; an active region overlying the n-type gallium and nitrogen containing material, a p-type gallium and nitrogen containing material; and a first transparent conductive oxide material overlying the p-type gallium and nitrogen containing material, and an interface region overlying the first transparent conductive oxide material. The method includes bonding the interface region to a handle substrate and subjecting the release material to an energy source to initiate release of the gallium and nitrogen containing substrate member.

A new optically pumped far infrared (FIR) laser with separate pump beam reflector and FIR output coupler is developed. The configuration of the new FIR laser greatly simplifies the tuning of the laser and enables the optimization of the pump beam absorption without affecting the laser alignment.

The present disclosure discloses a 2.8 ?m and 3.5 ?m dual-wavelength mid-infrared fiber laser, which employs 0.98 ?m+1.15 ?m pumping scheme, uses a fiber combiner to combine two pump lights into the double cladding Er-doped fluoride fiber. The Er ions in the ground state are first promoted to .sup.4I.sub.11/2 level by the 0.98 ?m pump light, realizing 2.8 ?m lasing based on .sup.4I.sub.11/2.fwdarw..sup.4I.sub.13/2 transition, and further promoted to .sup.4F.sub.9/2 level by the 1.15 ?m pump light, generating 3.5 ?m lasing based on .sup.4F.sub.9/2.fwdarw..sup.4I.sub.9/2 transition; followed by the 3.5 ?m laser transition, the Er ions would rapidly decay to .sup.4I.sub.11/2 level via non radiative transition, realizing the re-population of .sup.4I.sub.11/2 level, effectively enlarge the population inversion of 2.8 ?m transition, suppressing the self-termination of 2.8 ?m lasing and achieving 2.8 ?m and 3.5 ?m dual-wavelength cascaded lasing output.

The invention relates to an optoelectronic component (1) that is insensitive to dislocations, comprising:

a semiconductor heterostructure (2) able to emit laser radiation, said semiconductor heterostructure being formed from first semiconductors comprising a cascade of gain-providing active regions (21) in which the inter-band radiative transition is of type II, and

a carrier structure (30) comprising a non-native substrate (3) different from the first semiconductors, said semiconductor heterostructure (2) being formed by epitaxial growth on the carrier structure (30),

wherein the active regions have a dislocation density higher than 10.sup.7 .cm.sup.?2.