The present disclosure relates to a diode laser having reduced beam divergence. Some implementations reduce a beam divergence in the far field by means of a deliberate modulation of the real refractive index of the diode laser. An area of the diode laser (e.g., the injection zone), may be structured with different materials having different refractive indices. In some implementations, the modulation of the refractive index makes it possible to excite a supermode, the field of which has the same phase (in-phase mode) under the contacts. Light, which propagates under the areas of a lower refractive index, obtains a phase shift of π after passing through the index-guiding trenches. Consequently, the in-phase mode is supported and the formation of the out-of-phase mode is prevented. Consequently, the laser field can, in this way, be stabilized even at high powers such that only a central beam lobe remains in the far field.

The present technology can be used to control the current injection profile in the longitudinal direction of a high-power diode laser in order to optimize current densities as a function of position in the cavity to promote higher reliable output power and increase the electrical to optical conversion efficiency of the device beyond the level which can be achieved without application of this technique. This approach can be utilized, e.g., in the fabrication of semiconductor laser chips to improve the output power and wall plug efficiency for applications requiring improved performance operation.

A quantum cascade laser has an active layer, a first and second cladding layer, and an optical guide layer. The active layer has a plurality of injection quantum well regions and a plurality of light-emitting quantum well regions. The each of the injection quantum well regions and the each of the light-emitting quantum well regions are alternatively stacked. The first and second cladding layers are provided to interpose the active layer from both sides, and have a refractive index lower than an effective refractive index of the each of the light-emitting quantum well regions. The optical guide layer is disposed to divide the active layer into two parts. The optical guide layer has a refractive index higher than the effective refractive index of the each of the light-emitting quantum well regions, and has a thickness greater than the thickness of all well layers of quantum well layers.

A method for forming optical devices. The method includes providing a gallium nitride substrate member having a crystalline surface region and a backside region. The method also includes subjecting the backside region to a laser scribing process to form a plurality of scribe regions on the backside region and forming a metallization material overlying the backside region including the plurality of scribe regions. The method removes at least one optical device using at least one of the scribe regions.

The present disclosure provides a narrow-pulse-width pulse laser, including a circuit substrate, a laser chip, one or more capacitors, and a field effect transistor. Each of the field effect transistor, the capacitor, and the laser chip is electrically connected to the circuit substrate. The capacitors are arranged between the field effect transistor and the laser chip along an extension direction of a gap between the field effect transistor and the laser chip. The circuit substrate may include a first conductor layer; a second conductor layer; and an insulating layer arranged between the first conductor layer and the second conductor layer, wherein the first conductor layer and the second conductor layer are electrically connected through a via hole in the insulating layer.

An edge emitting laser bar is disclosed. In an embodiment an edge-emitting laser bar includes an AlInGaN-based semiconductor layer sequence having a contact side and an active layer configured to generate laser radiation, a plurality of individual emitters arranged next to each other and spaced apart from one another in a lateral transverse direction, each emitter configured to emit laser radiation and a plurality of contact elements arranged next to each other and spaced apart from one another in the lateral transverse direction on the contact side for making electrical contact with the individual emitters, each contact element being assigned to an individual emitter, wherein each contact element is electrically conductively coupled to the semiconductor layer sequence via a contiguous contact region of the contact side so that a current flow between the semiconductor layer sequence and the contact element is possible via the contact region.

A group III-nitride semiconductor device comprises a light emitting semiconductor structure comprising a p-type layer and an n-type layer operable as a light emitting diode or laser. On top of the p-type layer there is arranged an n+ or n++-type layer of a group III-nitride, which is transparent to the light emitted from the underlying semiconductor structure and of sufficiently high electrical conductivity to provide lateral spreading of injection current for the light-emitting semiconductor structure.

In an example, the present invention provides a gallium and nitrogen containing multilayered structure, and related method. The structure has a plurality of gallium and nitrogen containing semiconductor substrates, each of the gallium and nitrogen containing semiconductor substrates (“substrates”) having a plurality of epitaxially grown layers overlaying a top-side of each of the substrates. The structure has an orientation of a reference crystal direction for each of the substrates. The structure has a first handle substrate coupled to each of the substrates such that each of the substrates is aligned to a spatial region configured in a selected direction of the first handle substrate, which has a larger spatial region than a sum of a total backside region of plurality of the substrates to be arranged in a tiled configuration overlying the first handle substrate. The reference crystal direction for each of the substrates is parallel to the spatial region in the selected direction within 10 degrees or less. The structure has a first bonding medium provided between the first handle substrate and each of the substrate while maintaining the alignment between reference crystal orientation and the selected direction of the first handle substrate; and a processed region formed overlying each of the substrates configured concurrently while being bonded to the first handle substrate. Depending upon the embodiment, the processed region can include any combination of the aforementioned processing steps and/or steps.

A light-emitting device is provided. The light-emitting device is configured to emit a radiation and comprises: a substrate; an epitaxial structure on the substrate and comprising a first DBR stack, a light-emitting stack and a second DBR stack and a contact layer in sequence; an electrode; a current blocking layer between the contact layer and the electrode; a first opening formed in the current blocking layer; and a second opening formed in the electrode and within the first opening; wherein a part of the electrode fills in the first opening and contacts the contact layer; and the light-emitting device is devoid of an oxidized layer and an ion implanted layer in the second DBR stack.

A laser diode includes a semiconductor structure of a lower Bragg reflector layer, an active region, and an upper Bragg reflector layer. The upper Bragg reflector layer includes a lasing aperture having an optical axis oriented perpendicular to a surface of the active region. The active region includes a first material, and the lower Bragg reflector layer includes a second material, where respective lattice structures of the first and second materials are independent of one another. Related laser arrays and methods of fabrication are also discussed.