A method of forming an optical aperture of a vertical cavity surface emitting laser includes the steps of providing a layer stack of semiconductor layers, the semiconductor layers including an intermediate layer comprising a semiconductor material suitable to be oxidized and oxidizing the intermediate layer to an oxidation width so as to form an oxidized outer region and a non-oxidized central region in the intermediate layer. The method also includes removing at least a part of the oxidized outer region so as to form a gap where the oxidized outer region or the part of the oxidized outer region has been removed, depositing an electrically non-conducting material on walls of the gap with a thickness smaller than a thickness of the gap, and filling a remaining void of the gap with a further material.

A test apparatus has at least one optical source, a high-speed photodetector, a microcontroller or processor, and electrical circuitry to power and drive the optical source, high-speed photodetector, and microcontroller or processor. The apparatus measures the frequency response and optical path length of a multimode optical fiber under test, utilizes a reference VCSEL spatial spectral launch condition and modal-chromatic dispersion interaction data to estimate the channels total modal-chromatic bandwidth of the fiber under test, and computes and presents the estimated maximum data rate the fiber under test can support.

A test apparatus has at least one optical source, a high-speed photodetector, a microcontroller or processor, and electrical circuitry to power and drive the optical source, high-speed photodetector, and microcontroller or processor. The apparatus measures the frequency response and optical path length of a multimode optical fiber under test, utilizes a reference VCSEL spatial spectral launch condition and modal-chromatic dispersion interaction data to estimate the channels total modal-chromatic bandwidth of the fiber under test, and computes and presents the estimated maximum data rate the fiber under test can support.

A laser light source may include an arrangement of surface-emitting semiconductor lasers to which a voltage is applied such that an operating current is below the threshold current and an intrinsic emission of the surface-emitting semiconductor laser is prevented. The laser light source also comprises a first semiconductor laser which emits radiation that enters the surface-emitting semiconductor laser such that induced emission takes place via the injection locking mechanism and the individual surface-emitting semiconductor lasers emit laser light having the same wavelength and polarisation direction as the irradiated radiation. The emission frequency of the first semiconductor laser can be changed by changing the operating current.

A solid-state device, and use and formation thereof. The device includes a light emitter (102) that emits light with abeam propagation direction and includes an emitter epitaxial layer stack (940); a light routing medium (103) in optical communication with the light emitter; and a light detector (104) in optical communication with the light routing medium, which detects light emitted by the light emitter and includes a detector epitaxial stack (945). The light emitter and detector are monolithically formed on a semiconductor substrate. The emitter and detector epitaxial layer stacks include different pluralities of layers of a single epitaxial layer stack. The beam propagation direction is either in-plane with the single epitaxial layer stack and the light detector detects light out of plane with the single epitaxial layer stack, or out of plane with the single epitaxial layer stack and the light detector detects light in plane with the single epitaxial layer stack.

[Object] To provide a vertical cavity surface emitting laser element having a structure whose pitch can be narrowed, a vertical cavity surface emitting laser element array, a vertical cavity surface emitting laser module, and a method of producing a vertical cavity surface emitting laser element.

[Solving Means] A vertical cavity surface emitting laser element according to the present technology includes: a first substrate; and a second substrate. The first substrate is provided with a semiconductor layer including an active layer and a first distributed Bragg reflector (DBR) layer. The second substrate is provided with a constriction layer and a second DBR layer, the constriction layer having a constriction region and an injection region having conductivity higher than that of the constriction region, the second substrate being bonded to the first substrate such that the constriction layer is adjacent to the semiconductor layer.

A radiation-emitting semiconductor component is disclosed. In an embodiment, a component includes a semiconductor layer sequence and a carrier on which the semiconductor layer sequence is arranged, wherein the semiconductor layer sequence comprises an active region configured for generating radiation, an n-conducting mirror region and a p-conducting mirror region, wherein the active region is arranged between the n-conducting mirror region and the p-conducting mirror region, and wherein the p-conducting mirror region is arranged closer to the carrier than the active region.

A radiation-emitting semiconductor component is disclosed. In an embodiment, a component includes a semiconductor layer sequence and a carrier on which the semiconductor layer sequence is arranged, wherein the semiconductor layer sequence comprises an active region configured for generating radiation, an n-conducting mirror region and a p-conducting mirror region, wherein the active region is arranged between the n-conducting mirror region and the p-conducting mirror region, and wherein the p-conducting mirror region is arranged closer to the carrier than the active region.

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.

A multi junction vertical cavity surface emitting laser (VCSEL) may comprise a substrate, a top contact, and a stack comprising a set of layers formed between the substrate and the top contact. In some implementations, the set of layers formed between the substrate and the top contact may comprise a cavity comprising a first active region, a second active region, and a tunnel junction connecting the first active region and the second active region, a first distributed Bragg reflector (DBR) pair comprising a high-contrast p-type DBR (p-DBR) and a low-contrast p-DBR between the cavity and the top contact, and a second DBR pair comprising a high-contrast n-type DBR (n-DBR) and a low-contrast n-DBR between the cavity and the substrate. The low-contrast p-DBR and the low-contrast n-DBR are located on an inner side of the stack, and the high-contrast p-DBR and the high-contrast n-DBR are located on an outer side of the stack.