An optical semiconductor device outputting a predetermined wavelength of laser light includes a quantum well active layer positioned between a p-type cladding layer and an n-type cladding layer in thickness direction. The optical semiconductor device includes a separate confinement heterostructure layer positioned between the quantum well active layer and the n-type cladding layer. The optical semiconductor device further includes an electric-field-distribution-control layer positioned between the separate confinement heterostructure layer and the n-type cladding layer and configured by at least two semiconductor layers having band gap energy greater than band gap energy of a barrier layer constituting the quantum well active layer. The quantum well active layer is doped with 0.3 to 1×10.sup.18/cm.sup.3 of n-type impurity.

A laser source includes a topological cavity for nonreciprocal lasing, a magnetic material and an optical waveguide. The magnetic material is arranged to interact with the topological cavity. The optical waveguide is arranged to receive light extracted from the topological cavity upon breaking of time-reversal symmetry in the topological cavity.

An optical device is provided that includes an active waveguide having a top electrode and a plurality of layers including a gain layer. Configurations are disclosed for the active waveguide to enable amplification of a guided optical wave profile while preserving a shape of a lateral optical intensity profile of the guided optical wave as the guided optical wave is amplified along the waveguide. The top electrode and/or one or more layers of the active optical waveguide may be tailored to provide a tailored optical gain.

An embodiment semiconductor optical device includes an optical waveguide including a core, and an active layer extending in the waveguide direction of the optical waveguide for a predetermined distance and arranged in a state in which the active layer can be optically coupled to the core. The core and the active layer are arranged in contact with each other. The core is formed of a material with a refractive index of about 1.5 to 2.2, such as SiN, for example. In addition, the core is formed to a thickness at which a higher-order mode appears. The higher-order mode is an E.sub.12 mode, for example.

Systems and methods disclosed herein include a vertical cavity surface emitting laser (VCSEL) device that includes an anode, a cathode, and one or more curved apertures located in an epitaxial layer between the anode and the cathode, each of the one or more curved apertures having an aperture edge and one or more oxidation bridges crossing the curved aperture that allow current to flow inside the curved aperture, in which when a current signal is applied to the VCSEL, current flow between the anode and the cathode is distributed along the aperture edge of the one or more curved apertures.

In one example, a vertical cavity surface emitting laser (VCSEL) may include an active region to produce light at a wavelength, an emission surface to emit the light at the wavelength, a first oxide region spaced apart from the active region by a distance of at least a half-wavelength of the wavelength, a first oxide aperture in the first oxide region, a second oxide region between the first oxide region and the second oxide region, and a second oxide aperture in the second oxide region. The emitted light may have a divergence angle that is based on the respective positions and thicknesses of the first oxide region and the second oxide region.

An optical apparatus comprises a semiconductor substrate and a slab-coupled optical waveguide (SCOW) emitter disposed on the semiconductor substrate. The SCOW emitter comprises an optical waveguide comprising: a first region doped with a first conductivity type; a second region doped with a different, second conductivity type; and an optically active region disposed between the first region and the second region. The optically active region comprises a plurality of quantum dots.

An embodiment relates to a surface emitting laser device and a light emitting device including the same. The surface emitting laser device according to the embodiment may include a first reflective layer; an active layer disposed on the first reflective layer; an active region disposed on the active layer and having an aperture and an insulation region disposed around the aperture; and a second reflective layer disposed on the active region. The second reflective layer may include a core reflective layer disposed in a position vertically corresponding to the aperture. The embodiment may include a cladding insulation layer disposed around the core reflective layer. The horizontal cross-section of the aperture may be different from the horizontal cross-section of the core reflective layer.

The semiconductor laser element includes: a substrate; a first semiconductor layer disposed above a main surface of the substrate; an active layer that is disposed above the first semiconductor layer and generates light; and a second semiconductor layer) disposed above the active layer. In a top view of a front-side end portion of the semiconductor laser element from which the light is emitted, an end surface of the second semiconductor layer includes an inclined portion with respect to an end surface of the first semiconductor layer.

An optical apparatus comprises a semiconductor substrate and a slab-coupled optical waveguide (SCOW) emitter disposed on the semiconductor substrate. The SCOW emitter comprises an optical waveguide comprising: a first region doped with a first conductivity type; a second region doped with a different, second conductivity type; and an optically active region disposed between the first region and the second region. The optically active region comprises a plurality of quantum dots.