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 Group-III nitride light emitting device that utilizes scattering of hot carriers generated by Auger recombination from an externally electrically-driven, relatively narrow band gap carrier generation region into a relatively wide band gap carrier recombination region, such that the relatively wide band gap carrier recombination region of the Group-III nitride light emitting device is internally electrically injected by the hot carriers generated in the externally electrically-injected relatively narrow band gap carrier generation region. The device is used for generation of incoherent light (a light-emitting diode) or coherent light (a laser diode).

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 first burying layer burying a side of a first ridge structure is formed by selective growth using a first selective growth mask and a third selective growth mask. The first burying layer is formed by regrowth from a surface of a second semiconductor layer on a side of the first ridge structure. At the same time, by selective growth using a second selective growth mask and a fourth selective growth mask, a second burying layer burying a side of a second ridge structure is formed. The second burying layer is formed by regrowth from a surface of a fourth semiconductor layer on a side of the second ridge structure.

A vertical cavity surface emitting laser includes a first distributed Bragg reflector, an active layer, and a second distributed Bragg reflector. The first distributed Bragg reflector, the active layer and the second distributed Bragg reflector are arranged in sequence in the direction of a first axis. The second distributed Bragg reflector includes a semiconductor region and a high resistance region. The high resistance region has an electrical resistance higher than the electrical resistance of the semiconductor region. The first axis passes through the semiconductor region. The high resistance region surrounds the semiconductor region. In a cross section including the first axis, the high resistance region has an inner edge extending in a direction inclined with respect to the first axis such that an inner diameter of the high resistance region increases as a distance from the active layer increases in the direction of the first axis.

Example vertical cavity surface emitting lasers (VCSELs) include a mesa structure disposed on a substrate, the mesa structure including a first reflector, a second reflector defining at least one diameter, and an active cavity material structure disposed between the first and second reflectors; and a second contact layer disposed at least in part on top of the mesa structure and defining a physical emission aperture having a physical emission aperture diameter. The ratio of the physical emission aperture diameter to the at least one diameter is greater than or approximately 0.172 and/or the ratio of the physical emission aperture diameter to the at least one diameter is less than or approximately 0.36. An example VCSEL includes a substrate; a buffer layer disposed on a portion of the substrate; and an emission structure disposed on the buffer layer.

A Group III-Nitride quantum well laser including a distributed Bragg reflector (DBR). In some embodiments, the DBR includes Scandium. In some embodiments, the DBR includes Al.sub.1-xSc.sub.xN, which may have 0<x≤0.45.

A Vertical Cavity Surface Emitting Laser VCSEL, includes an optical resonator with a first reflector, a second reflector, and an active region for laser emission arranged between the first reflector and the second reflector and remaining regions outside of the active region, and an electrical contact arrangement configured to provide an electrical drive current to electrically pump the optical resonator. The optical resonator further comprises a loss layer introducing optical and/or electrical losses to increase wavelength shift of the laser emission when varying the drive current. If the loss layer is an optical loss layer, the optical losses introduced by the loss layer are higher than the sum of the optical losses in the remaining regions. If the loss layer is an electrical loss layer, the electrical losses introduced by the loss layer are higher by a factor of at least 5 than the electrical losses in the remaining regions.

The present disclosure provides a semiconductor device. The semiconductor device includes a substrate having a first side and a second side opposite to the first side; a first optical element at the first side of the substrate; and a semiconductor stack on the substrate. The semiconductor stack includes a first reflective structure; a second reflective structure; a cavity region between the first reflective structure and the second reflective structure and having a first surface and a second surface opposite to the first surface; and a confinement layer in one of the second reflective structure and the first reflective structure. The semiconductor device further includes a first electrode and a second electrode on the first surface.

In an optical device, a first semiconductor layer and a second semiconductor layer are formed to be thinner than a core, an active layer has a shape with an end in a waveguide direction tapers toward a tip end, the first semiconductor layer having a trapezoidal shape with a width thereof decreases toward a side of a third semiconductor layer from a side of the core in a plan view and a width thereof decreases as one end in the waveguide direction recedes from a central portion of the active region, and the second semiconductor layer having a trapezoidal shape with a width thereof decreases toward a side of a fourth semiconductor layer from the side of the core in a plan view and a width thereof decreases as one end in the waveguide direction recedes from the central portion of the active region.