A method of producing a laser diode bar includes producing a plurality of emitters arranged side by side, emitters each including a semiconductor layer sequence having an active layer that generates laser radiation, a p-contact on a first main surface of the laser diode bar and an n-contact on a second main surface of the laser diode bar opposite the first main surface, testing at least one optical and/or electrical property of the emitters, wherein emitters in which the optical and/or electrical property lies within a predetermined setpoint range are assigned to a group of first emitters, and emitters in which the at least one optical and/or electrical property lies outside the predetermined setpoint range are assigned to a group of second emitters, and electrically contacting first emitters, wherein second emitters are not electrically contacted so that they are not supplied with current during operation of the laser diode bar.

A VCSEL device includes a first electrical contact, a substrate, a second electrical contact, and an optical resonator arranged on a first side of the substrate. The optical resonator includes a first reflecting structure comprising a first distributed Bragg reflector, a second reflecting structure comprising a second distributed Bragg reflector, an active layer arranged between the first and second reflecting structures, and a guiding structure. The guiding structure is configured to define a first relative intensity maximum of an intensity distribution within the active layer at a first lateral position such that a first light emitting area is provided, to define at least a second relative intensity maximum of the intensity distribution within the active layer at a second lateral position such that a second light emitting area is provided, and to reduce an intensity in between the at least two light-emitting areas during operation.

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.

A light source device in which a plurality of semiconductor light-emitting elements are disposed, each of the plurality of semiconductor light-emitting elements being configured with a first reflector, a resonator cavity including an active layer, and a second reflector which are stacked in this sequence on a semiconductor substrate, wherein in each of the semiconductor light-emitting elements, an electric contact region for supplying carriers to the active layer is disposed on a surface of the second reflector on an opposite side thereof to the active layer, and wherein the plurality of semiconductor light-emitting elements include a first semiconductor light-emitting element of which shape of the contact region is a first shape, and a second semiconductor light-emitting element of which shape of the contact region is a second shape which is different from the first shape.

Disclosed is a surface etched grating semiconductor laser with periodic pumping structure. The structure includes a lower doped dielectric layer, a multiple quantum well active layer, a ridge-shaped doped dielectric layer, periodic grating grooves formed on the ridge-shaped doped dielectric layer and a top electrical contact layer forming ohmic electrical contact with electrical contact regions between the grating grooves. Carriers are injected through the periodic electrical contact layer, flow through the electrical contact regions, spread laterally when reaching the bottom of the grating grooves, and then continue to spread to the multiple quantum well active layer. In a case of uniform distribution, a laser based on refractive index modulation is realized. In a case of non-uniform distribution, a laser with mixed modulation is realized by introducing additional gain modulation.

In some implementations, a vertical cavity surface emitting laser (VCSEL) device includes a substrate; a first mirror disposed over the substrate; a bonding layer disposed over the first mirror; and an active region disposed over the bonding layer. The substrate is a gallium arsenide (GaAs) substrate, and the active region is an indium phosphide (InP)-based active region.

An optoelectronic semiconductor device includes a semiconductor body in which an active layer configured to generate or detect electromagnetic radiation, a first interlayer and a p-conducting contact layer are formed, and a connection layer applied to the semiconductor body, wherein the contact layer is disposed between the first interlayer and the connection layer and adjoins the connection layer, the active layer is arranged on a side of the first interlayer remote from the contact layer, the first interlayer and the contact layer are based on a nitride compound semiconductor, the contact layer is doped with a p-dopant, the contact layer has a thickness of at most 50 nm, and the contact layer includes a lower aluminum content than the first interlayer.

A manufacturing method for semiconductor device comprises the steps of: forming a ridge on the surface of an InP substrate; applying a photoresist to the surface of the InP substrate so as to cover the ridge; exposing through a mask an area of the photoresist covering part of an electrode contact layer at the top of the ridge, to form a resist pattern by development; applying a shrink material so as to cover resist pattern defects occurred when forming the resist pattern; forming a crosslinked portion in the defects to repair them by reacting the shrink material with an acid remaining at the exposed interface of the resist pattern; and removing by etching an electrode contact layer exposed from the resist pattern having the repaired defects after stripping away an unreacted shrink material, thereby to obtain a desired processed shape.

Visible spectrum quantum dot (QD) light emitting sources integrable with integrated silicon photonics include a plurality of epitaxially grown InP QDs within an active region. The light emitting sources include light emitting diodes (LEDs) and semiconductor lasers.

A power over fiber system includes a power sourcing equipment, a powered device, an optical fiber cable, a measurer and a control device. The power sourcing equipment includes a semiconductor laser that oscillates with electric power, thereby outputting feed light. The powered device includes a photoelectric conversion element that converts the feed light into electric power. The optical fiber cable transmits the feed light from the power sourcing equipment to the powered device. The measurer measures a distance from the power sourcing equipment to the powered device. The control device controls the power sourcing equipment to output the feed light by changing a laser wavelength thereof for the distance from the power sourcing equipment to the powered device measured by the measurer.