A Group-III nitride light emitting device that utilizes scattering of hot carriers generated by Auger recombination from an externally electrically-driven, relatively narrow band gap carrier generation region into a relatively wide band gap carrier recombination region, such that the relatively wide band gap carrier recombination region of the Group-III nitride light emitting device is internally electrically injected by the hot carriers generated in the externally electrically-injected relatively narrow band gap carrier generation region. The device is used for generation of incoherent light (a light-emitting diode) or coherent light (a laser diode).

A Group-III nitride light emitting device that utilizes scattering of hot carriers generated by Auger recombination from an externally electrically-driven, relatively narrow band gap carrier generation region into a relatively wide band gap carrier recombination region, such that the relatively wide band gap carrier recombination region of the Group-III nitride light emitting device is internally electrically injected by the hot carriers generated in the externally electrically-injected relatively narrow band gap carrier generation region. The device is used for generation of incoherent light (a light-emitting diode) or coherent light (a laser diode).

An optical system comprising an optoelectronic device having a facet and a coating on the facet. The facet is configured to be in optical communication with at least a first optical medium during a first time period and a second optical medium during a second time period. The first optical medium has a first refractive index and the second optical medium has a second refractive index different from the first refractive index. The coating is configured to provide a first reflectance during the first time period for optical signals in a predetermined wavelength range and to provide a second reflectance during the second time period for optical signals in the predetermined wavelength range wherein the second reflectance is equal to the first reflectance within a negligible margin for optical signals having at least one wavelength in the predetermined wavelength range.

A dummy bar is used to deposit an insulating film on a front end face (32) and a rear end face (34) of a laser diode bar (30), the dummy bar including a body part (12) having a plate shape, and including a pair of side surfaces (14), an upper surface (16), and a lower surface (18), the body part having a longitudinal length equal to a longitudinal length of the laser diode bar (30), the pair of side surfaces (14) being orthogonal to a longitudinal direction and opposite each other, the upper surface (16) and the lower surface (18) being orthogonal to the pair of side surfaces, parallel to a thickness direction of the plate shape, and opposite each other and a handle part (20) provided at a position separated from the lower surface (18) on each of the pair of side surfaces (14).

A dummy bar is used to deposit an insulating film on a front end face (32) and a rear end face (34) of a laser diode bar (30), the dummy bar including a body part (12) having a plate shape, and including a pair of side surfaces (14), an upper surface (16), and a lower surface (18), the body part having a longitudinal length equal to a longitudinal length of the laser diode bar (30), the pair of side surfaces (14) being orthogonal to a longitudinal direction and opposite each other, the upper surface (16) and the lower surface (18) being orthogonal to the pair of side surfaces, parallel to a thickness direction of the plate shape, and opposite each other and a handle part (20) provided at a position separated from the lower surface (18) on each of the pair of side surfaces (14).

An inorganic coating may be applied to bond optically scattering particles or components. Optically scattering particles bonded via the inorganic coating may form a three dimensional film which can receive a light emission, convert, and emit the light emission with one or more changed properties. The inorganic coating may be deposited using a low-pressure deposition technique such as an atomic layer deposition (ALD) technique. Two or more components, such as an LED and a ceramic phosphor layer may be bonded together by depositing an inorganic coating using the ALD technique.

An inorganic coating may be applied to bond optically scattering particles or components. Optically scattering particles bonded via the inorganic coating may form a three dimensional film which can receive a light emission, convert, and emit the light emission with one or more changed properties. The inorganic coating may be deposited using a low-pressure deposition technique such as an atomic layer deposition (ALD) technique. Two or more components, such as an LED and a ceramic phosphor layer may be bonded together by depositing an inorganic coating using the ALD technique.

A nitride semiconductor laser element includes a stacked structure and a dielectric multilayer film, The dielectric multilayer film includes a first dielectric film, a second dielectric film, and a third dielectric film in the stated order. The nitride semiconductor laser element satisfies the following expressions:

[00001]$.Math.\mathrm{nk}\times \mathrm{dk}+\mathrm{ni}\times \mathrm{di}+\mathrm{nj}\times \mathrm{dj}=m1\times \frac{\lambda }{4}\pm \frac{\lambda }{16};$$\mathrm{nj}\times \mathrm{dj}=m2\times \lambda /4\pm \lambda /16;\mathrm{and}$$\frac{3\lambda }{16}\leqq .Math.\mathrm{nk}\times \mathrm{dk}\leqq \frac{5\lambda }{16}.$

A nitride semiconductor laser element includes a stacked structure and a dielectric multilayer film, The dielectric multilayer film includes a first dielectric film, a second dielectric film, and a third dielectric film in the stated order. The nitride semiconductor laser element satisfies the following expressions:

[00001]$.Math.\mathrm{nk}\times \mathrm{dk}+\mathrm{ni}\times \mathrm{di}+\mathrm{nj}\times \mathrm{dj}=m1\times \frac{\lambda }{4}\pm \frac{\lambda }{16};$$\mathrm{nj}\times \mathrm{dj}=m2\times \lambda /4\pm \lambda /16;\mathrm{and}$$\frac{3\lambda }{16}\leqq .Math.\mathrm{nk}\times \mathrm{dk}\leqq \frac{5\lambda }{16}.$

Building blocks are provided for on-chip chemical sensors and other highly-compact photonic integrated circuits combining interband or quantum cascade lasers and detectors with passive waveguides and other components integrated on a III-V or silicon. A MWIR or LWIR laser source is evanescently coupled into a passive extended or resonant-cavity waveguide that provides evanescent coupling to a sample gas (or liquid) for spectroscopic chemical sensing. In the case of an ICL, the uppermost layer of this passive waveguide has a relatively high index of refraction that enables it to form the core of the waveguide, while the ambient air, consisting of the sample gas, functions as the top cladding layer. A fraction of the propagating light beam is absorbed by the sample gas if it contains a chemical species having a fingerprint absorption feature within the spectral linewidth of the laser emission.