A quantum cascade laser element includes: a semiconductor substrate; a semiconductor laminate having a first end surface and a second end surface; a first electrode; a second electrode; and an anti-reflection film formed on the first end surface. The semiconductor laminate is configured to oscillate laser light having a center wavelength of 7.5 μm or more. The anti-reflection film includes an insulating film being a CeO.sub.2 film formed on the first end surface, a first refractive index film being a YF.sub.3 film or a CeF.sub.3 film disposed on a side opposite the first end surface with respect to the insulating film, and a second refractive index film formed on the first refractive index film on a side opposite the first end surface with respect to the first refractive index film and having a refractive index of larger than 1.8.

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 radiation-emitting semiconductor chip includes a semiconductor layer sequence having an active layer for generating electromagnetic radiation. The semiconductor chip also includes a reflector at a side surface of the semiconductor layer sequence having a reflector surface facing the semiconductor layer sequence and extending obliquely with respect to the active layer. The semiconductor chip further includes a top surface extending transversely with respect to the reflector surface and having a first emission region. The semiconductor chip additionally includes a further reflector situated opposite the reflector. The semiconductor chip is configured such that electromagnetic radiation generated in the active layer during operation is reflected by the reflector and emerges from the semiconductor chip via the emission region of the top surface. A main emission direction of the emerging electromagnetic radiation together with the active layer form an emergence angle of between 30° and 80° inclusive.

A laser device includes a gain medium including a facet. The laser device includes a metasurface including a plurality of supercells. The metasurface is disposed on a substrate and configured to reflect and focus a first portion of light from the facet back to the gain medium as a feedback beam. The metasurface can be configured to reflect a second portion of the light as an output beam at an angle that is nonzero relative to a direction of the feedback beam. The metasurface can be configured to transmit a second portion of the light as an output beam through the metasurface away from the facet. The emission wavelength of the laser device can be tuned by translating the metasurface. The output beam can be collimated towards a fixed direction while tuning the wavelength.

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.

An apparatus for stacking and coating of very short cavity laser diode arrays. The apparatus includes an array holder fixture to securely hold the very short cavity laser diode arrays and spacer arrays, and a stacking plate. The array holder fixture including a top-side presser to secure a stack of very short cavity laser arrays and spacer arrays from a first end of the stack, a bottom-side presser to secure the stack of very short cavity laser arrays and spacer arrays from a second end of the stack, and a pair of side clamps. The array holder fixture is operatively coupled to the stacking plate during the stacking of the very short cavity laser diode arrays and spacer arrays.

Provided in a method of fabricating an optical element array including providing a silicon substrate, providing a first element layer on the silicon substrate, the first element layer including a plurality of passive optical elements, providing a plurality of semiconductor blocks on a compound semiconductor wafer, providing semiconductor dies by dicing the compound semiconductor wafer by the plurality of semiconductor blocks, and providing a second element layer by providing the semiconductor dies on the first element layer, each of the plurality of semiconductor blocks contacting at least one corresponding passive optical element from among the plurality of passive optical elements.

The invention relates to methods of producing a cap substrate, to methods of producing a packaged radiation-emitting device at the wafer level, and to a radiation-emitting device. By producing a cap substrate, providing a device substrate in the form of a wafer including a multitude of radiation-emitting devices, arranging the substrates one above the other such that the substrates are bonded along an intermediate bonding frame, and dicing the packaged radiation-emitting devices, improved packaged radiation-emitting devices are provided which are advantageously arranged within a cavity free from organics and can be examined, still at the wafer level, in terms of their functionalities in a simplified manner prior to being diced.

The invention relates to methods of producing a cap substrate, to methods of producing a packaged radiation-emitting device at the wafer level, and to a radiation-emitting device. By producing a cap substrate, providing a device substrate in the form of a wafer including a multitude of radiation-emitting devices, arranging the substrates one above the other such that the substrates are bonded along an intermediate bonding frame, and dicing the packaged radiation-emitting devices, improved packaged radiation-emitting devices are provided which are advantageously arranged within a cavity free from organics and can be examined, still at the wafer level, in terms of their functionalities in a simplified manner prior to being diced.