A method for making a device. The method comprises forming a buffer layer on a substrate; forming a periodically doped layer on the buffer layer; forming one or more wires on the periodically doped layer, the wires being chosen from nanowires and microwires; and introducing porosity into the periodically doped layer to form a porous distributed Bragg reflector (DBR). Various devices that can be made by the method are also disclosed.

A light emitting device includes a substrate, a laminated structure provided to the substrate, and including a plurality of columnar parts, and an electrode disposed at an opposite side to the substrate of the laminated structure, wherein the columnar parts have a light emitting layer, the columnar parts are disposed between the electrode and the substrate, light generated in the light emitting layer propagates through the plurality of columnar parts to cause laser oscillation, and the electrode is provided with a hole.

An optical semiconductor device includes an active layer having a plurality of quantum dot layers. The plurality of quantum dot layers include: a first quantum dot layer doped with a p-type impurity; and a second quantum dot layer doped with an n-type impurity and having an emission wavelength different from that of the first quantum dot layer.

An optical apparatus comprises a semiconductor substrate, and a supermode filtering waveguide (SFW) emitter disposed on the semiconductor substrate. The SFW emitter comprises a first optical waveguide, a spacer layer, and a second optical waveguide spaced apart from the first optical waveguide by the spacer layer. The second optical waveguide is evanescently coupled with the first optical waveguide and is configured, in conjunction with the first waveguide, to selectively propagate only a first mode of a plurality of optical modes. The SFW emitter further comprises an optically active region disposed in one of the first optical waveguide and the second optical waveguide.

A method of making a Group III nitride material that includes: providing a substrate; patterning a template on the substrate; depositing a layer of a material comprising aluminum, gallium and nitrogen on the substrate at a temperature; annealing the layer comprising aluminum, gallium and nitrogen; epitaxially growing Distributed Bragg Reflectors to form a structure on the substrate that comprises microcavities; and etching micropillars in the structure for at least 30 seconds with a heated basic solution is described.

A device, such as a light-emitting device, e.g. a laser device, comprising: a plurality of group III-V semiconductor NWs grown on one side of a graphitic substrate, preferably through the holes of an optional hole-patterned mask on said graphitic substrate; a first distributed Bragg reflector or metal mirror positioned substantially parallel to said graphitic substrate and positioned on the opposite side of said graphitic substrate to said NWs; optionally a second distributed Bragg reflector or metal mirror in contact with the top of at least a portion of said NWs; and wherein said NWs comprise aim-type doped region and a p-type doped region and optionally an intrinsic region there between.

A semiconductor structure comprising a matrix having a first cubic Group-III nitride with a first band gap, and a second cubic Group-III nitride having a second band gap and forming a region embedded within the matrix. The second cubic Group-III nitride comprises an alloying material which reduces the second band gap relative to the first band gap, a quantum wire is defined by a portion within the region embedded within the matrix, the portion forming a one-dimensional charge-carrier confinement channel, wherein the quantum wire is operable to exhibit emission luminescence which is optically polarised.

The light emitting device includes a substrate, and a laminated structure provided to the substrate, and including a plurality of columnar parts, wherein the columnar part includes a first semiconductor layer, a second semiconductor layer different in conductivity type from the first semiconductor layer, and a light emitting layer disposed between the first semiconductor layer and the second semiconductor layer, the laminated structure includes a third semiconductor layer which is connected to an opposite side to the substrate of the second semiconductor layer, and is same in conductivity type as the second semiconductor layer, the second semiconductor layer is disposed between the light emitting layer and the third semiconductor layer, the third semiconductor layer is provided with a recessed part, an opening of the recessed part is provided to a surface at an opposite side to the substrate side of the third semiconductor layer, and a diametrical size in a bottom of the recessed part is smaller than a diametrical size in the opening of the recessed part.

An optical apparatus comprises a semiconductor substrate, and a supermode filtering waveguide (SFW) emitter disposed on the semiconductor substrate. The SFW emitter comprises a first optical waveguide, a spacer layer, and a second optical waveguide spaced apart from the first optical waveguide by the spacer layer. The second optical waveguide is evanescently coupled with the first optical waveguide and is configured, in conjunction with the first waveguide, to selectively propagate only a first mode of a plurality of optical modes. The SFW emitter further comprises an optically active region disposed in one of the first optical waveguide and the second optical waveguide.

A light emitting device includes a substrate, a laminated structure provided to the substrate, and including a plurality of columnar parts, and a covering part configured to cover the laminated structure, wherein the columnar parts have a light emitting layer, and the covering part is provided with a through hole penetrating the covering part.