Structures and methods for forming highly uniform and high-porosity gallium-nitride layers with sub-100-nm pore sizes are described. Electrochemical etching of heavily-doped gallium nitride at low bias voltages in concentrated nitric acid is used to form the porous gallium nitride. The porous layers may be used in reflective structures for integrated optical devices such as VCSELs and LEDs.

Structures and methods for forming highly uniform and high-porosity gallium-nitride layers with sub-100-nm pore sizes are described. Electrochemical etching of heavily-doped gallium nitride at low bias voltages in concentrated nitric acid is used to form the porous gallium nitride. The porous layers may be used in reflective structures for integrated optical devices such as VCSELs and LEDs.

Apparatuses and methods for a temperature insensitive electro-absorption modulator and laser. The device comprising a laser capable of emitting light. The laser itself includes a laser gain section, a first mirror and a second mirror. Each of the mirrors are coupled to the laser gain section. The laser gain section contains quantum wells. The first mirror and the second mirror have a wavelength bandwidth sufficient for a lasing wavelength range of the laser. A modulator is coupled to the laser to receive the light and is capable of modulating the light to vary the output from the modulator. The modulator contains quantum wells and has a quantum well confinement factor that is greater than 0.1. An output coupler is coupled to the modulator and the output coupler has a back reflection that is less than half of a back reflection of the second mirror. The laser has a lasing wavelength that tracks the absorption spectrum of the modulator. The device is operated at a temperature range comprising a first temperature and a second temperature, wherein the second temperature is greater than the first temperature by at least 15 degrees Celsius.

The present invention relates to a semiconductor laser for use in an optical module for measuring distances and/or movements, using the self-mixing effect. The semiconductor laser comprises a layer structure including an active region (3) embedded between two layer sequences (1, 2) and further comprises a photodetector arranged to measure an intensity of an optical field resonating in said laser. The photodetector is a phototransistor composed of an emitter layer (e), a collector layer (c) and a base layer (b), each of which being a bulk layer and forming part of one of said layer sequences (1, 2). With the proposed semiconductor laser an optical module based on this laser can be manufactured more easily, at lower costs and in a smaller size than known modules.

The present invention relates to a semiconductor laser for use in an optical module for measuring distances and/or movements, using the self-mixing effect. The semiconductor laser comprises a layer structure including an active region (3) embedded between two layer sequences (1, 2) and further comprises a photodetector arranged to measure an intensity of an optical field resonating in said laser. The photodetector is a phototransistor composed of an emitter layer (e), a collector layer (c) and a base layer (b), each of which being a bulk layer and forming part of one of said layer sequences (1, 2). With the proposed semiconductor laser an optical module based on this laser can be manufactured more easily, at lower costs and in a smaller size than known modules.

A vertical cavity surface emitting laser (VCSEL) including a substrate and a bottom distributed Bragg reflector (DBR) having a plurality of layers deposited on the substrate. The VCSEL also includes a first charge confining layer deposited on the bottom DBR, an active region deposited on the first charge confining layer, and a second charge confining layer deposited on the active region. A current blocking layer is provided on the second charge confining layer, and a top epitaxial DBR including a plurality of top epitaxial DBR layers is deposited on the current blocking layer. A top electrode is deposited on the top epitaxial DBR, a bottom electrode is deposited on the bottom DBR and adjacent to the active region, and a top dielectric DBR is deposited on the top epitaxial DBR and the top electrode.

The subject invention includes a semiconductor laser with the laser having a DBR mirror on a substrate, a quantum well on the DBR mirror, and an interior CGH with a back propagated output for emitting a large sized Gaussian and encircling high energy. The DBR mirror has a plurality of GaAs/AlGaAs layers, while the quantum well is composed of AlGaAs/InGaAs. The CGH is composed of AlGaAs.

Ina light emitting device, a first diametrical size that is the largest size of a columnar part between a substrate side of a light emitting layer and an opposite side of the substrate, the columnar part has a size no larger than the first diametrical size in an area between the substrate side of the light emitting layer and the substrate side of a first semiconductor layer, the columnar part has a size smaller than the first diametrical size in the area between the substrate side of the light emitting layer and the substrate side of the first semiconductor layer, the columnar part has a size no larger than the first diametrical size in an area between the opposite side to the substrate of the light emitting layer, and an opposite side to the substrate of a second semiconductor layer, and the columnar part has a size smaller than the first diametrical size in the area between the opposite side to the substrate of the light emitting layer in the laminating direction, and the opposite side to the substrate of the second semiconductor layer.

A two-dimensional photonic-crystal surface-emitting laser includes an active layer, a two-dimensional photonic crystal, and electrodes. The two-dimensional photonic crystal contains a plate-shaped base material arranged on one side of the active layer and different refractive index portions arranged at lattice points of a predetermined lattice in the base material and having a refractive index different from that of the base material, a band edge frequency for each position in an electric current supply region, which is at least a part of the two-dimensional photonic crystal, is monotonically increased in one direction parallel to the base material. Such a two-dimensional photonic crystal occurs when the different refractive index portion has a refractive index smaller than that of the base material, a filling factor, which is a ratio of a volume occupied by the different refractive index portion in a unit lattice constituting the lattice, is monotonically increased in the one direction.

A surface light-emission type semiconductor light-emitting device includes a first semiconductor layer; a light-emitting layer provided on the first semiconductor layer; a second semiconductor layer provided on the light-emitting layer; an uneven structure provided on the second semiconductor layer, the uneven structure including a protrusion and a recess next to the protrusion; a first metal layer covering the uneven structure; and a second metal layer provided between the uneven structure and the first metal layer. The second metal layer is provided on one of a bottom surface of the recess, an upper surface of the protrusion, or a side surface of the protrusion. The second metal layer has a reflectance for light radiated from the light-emitting layer, which is less than a reflectance of the first metal layer for the light.