A semiconductor device includes a substrate, a first type semiconductor structure, semiconductor columnar bodies between the substrate and the first type semiconductor structure, a first electrode and a second electrode. The first type semiconductor structure includes a first surface, a second surface opposite the first surface and away from the substrate, a first extension and a second extension respectively extending outward beyond the semiconductor columnar bodies. The first electrode and the second electrode are on the second surface of the first type semiconductor structure.

A semiconductor device includes a substrate, a first type semiconductor structure, semiconductor columnar bodies between the substrate and the first type semiconductor structure, a first electrode and a second electrode. The first type semiconductor structure includes a first surface, a second surface opposite the first surface and away from the substrate, a first extension and a second extension respectively extending outward beyond the semiconductor columnar bodies. The first electrode and the second electrode are on the second surface of the first type semiconductor structure.

A grating coupler with a wafer bonded configuration includes: a substrate; an oxide layer disposed on the substrate; a silicon nitride layer disposed above the oxide layer; a first silicon layer disposed above the silicon nitride layer; a second silicon layer disposed above the first silicon layer; and a bi-layer grating disposed above the silicon nitride layer. The bi-layer grating includes (i) a first etched layer of the first silicon layer and (ii) a second etched layer of the second silicon layer.

A grating coupler with a wafer bonded configuration includes: a substrate; an oxide layer disposed on the substrate; a silicon nitride layer disposed above the oxide layer; a first silicon layer disposed above the silicon nitride layer; a second silicon layer disposed above the first silicon layer; and a bi-layer grating disposed above the silicon nitride layer. The bi-layer grating includes (i) a first etched layer of the first silicon layer and (ii) a second etched layer of the second silicon layer.

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 photodetector is positioned so that imaginary lines perpendicular to an emission end surface of a first light-emitting element through first and second points, respectively, pass through the photodetector. The first and second points are two points at which an imaginary line parallel to the emission end surface through an inside of an outer edge of the first light-emitting element intersects the outer edge of the first light-emitting element in a top view. At least a part of a first wiring region is arranged in a first region between imaginary lines perpendicular to the emission end surface through third and fourth points, respectively. The third and fourth points are two points at which an imaginary line parallel to the emission end surface through an inside of an outer edge of the photodetector intersects the outer edge of the photodetector in the top view.

There are provided high power, high brightness solid-state laser systems that maintain initial beam properties, including power levels, and do not have degradation of performance or beam quality, for at least 10,000 hours of operation. There are provided high power, high brightness solid-state laser systems containing Oxygen in their internal environments and which are free from siloxanes.

In an embodiment a semiconductor laser component includes a plurality of semiconductor lasers, each of the semiconductor lasers configured to emit primary electromagnetic radiation of a primary spectral bandwidth in a visible wavelength range and a beam combiner configured to combine the primary electromagnetic radiations emitted from the semiconductor lasers, form secondary electromagnetic radiation from a superposition of the primary electromagnetic radiations of the semiconductor lasers and couple the secondary electromagnetic radiation out from the beam combiner, wherein the secondary electromagnetic radiation has a secondary spectral bandwidth that is at least twice as large as an average value of the primary spectral bandwidths.

In an embodiment a semiconductor laser component includes a plurality of semiconductor lasers, each of the semiconductor lasers configured to emit primary electromagnetic radiation of a primary spectral bandwidth in a visible wavelength range and a beam combiner configured to combine the primary electromagnetic radiations emitted from the semiconductor lasers, form secondary electromagnetic radiation from a superposition of the primary electromagnetic radiations of the semiconductor lasers and couple the secondary electromagnetic radiation out from the beam combiner, wherein the secondary electromagnetic radiation has a secondary spectral bandwidth that is at least twice as large as an average value of the primary spectral bandwidths.

A light pulse source and method for generating repetitive optical pulses are described. The light pulse source includes a continuous wave cw laser device, an optical waveguide optically coupled with the laser device, an optical microresonator, and a tuning device. The optical microresonator coupling cw laser light via the waveguide into the microresonator, which, may include, a light field in a soliton state with soliton shaped pulses coupled out of the microresonator for providing the repetitive optical pulses. The laser device includes a chip based semiconductor laser, the microresonator and/or the waveguide may reflect an optical feedback portion of light back to the semiconductor laser, which may provide self-injection locking relative to a resonance frequency of the microresonator. The tuning device is arranged for tuning at least one of a driving current and a temperature of the semiconductor laser such that the microresonator may provide the soliton state.