A semiconductor optical device that achieves both of heat dissipation and light confinement and permits efficient current injection or application of an electric field is implemented. The semiconductor optical device includes: a core layer including an active region (1) made of a compound semiconductor; two cladding layers (5, 6) injecting current into the core layer; and a third cladding layer (4) made of a material having a larger thermal conductivity, a smaller refractive index, and a larger band gap than a material for any of the core layer and the two cladding layers.

A semiconductor laser (1) is provided that includes a semiconductor layer sequence in which an active zone for generating laser radiation is located. A ridge waveguide is formed as an elevation from the semiconductor layer sequence. An electrical contact layer is located directly on the ridge waveguide. A metallic electrical connection region is located directly on the contact layer and is configured for external electrical connection of the semiconductor laser. A metallic breakage coating extends directly to facets of the semiconductor layer sequence and is arranged on the ridge waveguide. The breakage coating is electrically functionless and includes a lower speed of sound for a breaking wave than the semiconductor layer sequence in the region of the ridge waveguide.

Embodiments are directed to the fabrication of an electro-optical device. The device comprises the forming of an active region with a stack of III-V semiconductor gain materials stacked along a stacking direction z. The active region may be formed as a slab having several lateral surface portions, each extending parallel to the stacking direction z. The device further comprises selectively re-growing two paired elements, which include: a pair of doped layers of III-V semiconductor materials (an n-doped layer and a p-doped layer); and a pair of lateral waveguide cores. The two paired elements may be laterally arranged, two-by-two, on opposite sides of the slab. The elements distinctly adjoin respective ones of the lateral surface portions of the slab, so as for these elements to be separated from each other by the slab. The disclosure may be further directed to related silicon photonics devices.

A method is presented for forming a germanium (Ge) laser diode with direct bandgap for laser generation. The method includes forming an intrinsic Ge active layer over a substrate, forming a p+ region and an n+ region adjacent the intrinsic Ge active layer, such that the p+ region, the n+ region, and the intrinsic Ge active layer collectively define a p-i-n diode, and forming metal contacts to the p+ and n+ regions.

A first conduction type first cladding layer and a second conduction type second cladding layer are arranged on the two sides in the vertical direction of a core portion having a multiple quantum-well structure, and a first conduction type third cladding layer and a second conduction type fourth cladding layer are arranged on the two sides in the horizontal direction of the core portion. A first electrode connected to the third cladding layer is formed. A second electrode connected to the fourth cladding layer is formed. A reverse bias is applied between the first and third cladding layers and the second and fourth cladding layers.

A vertical cavity surface emitter device (e.g., VCSEL or RC-LED) containing a buried index-guiding current confinement aperture layer which is grown, and lithographically processed to define position, shape and dimension of an inner aperture. In a regrowth process, the aperture is filled with a single crystalline material from the third contact layer. The aperture provides for both current and optical confinement, while allowing for higher optical power output and improved thermal conductivity.

A light source comprises a GeSn active zone inserted between two contact zones. The active zone is formed directly on a silicon oxide layer by a first lateral epitaxial growth of a Ge germination layer followed by a second lateral epitaxial growth of a GeSn base layer. A cavity is formed between the contact zones by encapsulation and etching, so as to guide these lateral growths. A vertical growth of GeSn is then achieved from the base layer to form a structural layer. The active zone is formed in the stack of base and structural layers.

The invention relates to a laser system comprising a laser light source (1) that emits laser radiation during operation of the laser system, a modulation means (2) that brings about modulation of the laser radiation emitted by the laser light source (1) such that the spectrum of the laser radiation comprises a carrier (14) and two sidebands (13, 15) that are symmetrically distributed around the carrier, and at least one optical amplifier (5) that amplifies the radiation emitted by the laser light source (1). The invention proposes that an optical filter (4) be provided in the beam path of the laser radiation, upstream of the optical amplifier (5), which filter is intended for removing the spectral portion of the laser radiation at the frequency of one of the two sidebands (13). The laser system is suitable inter alia for generating an artificial guide star (laser guide star) for astronomical telescopes comprising adaptive optics. The invention furthermore relates to a method for generating single-sideband modulated laser radiation.

A semiconductor optical element is configured to emit or absorb light and includes a lower structure that includes a multiple quantum well layer; an upper mesa structure that is disposed on the lower structure; a current injection structure that is disposed on the upper mesa structure, when seen from an optical axis of the emitted or absorbed light, a width of a portion of the current injection structure in contact with the upper mesa structure is smaller than a width of the upper mesa structure, the portion of the current injection structure in contact with the upper mesa structure consisting of InP, and an average refractive index of the upper mesa structure is higher than a refractive index of the InP forming the current injection structure; and an insulating film covering both side surfaces of the upper mesa structure and a part of an upper surface of the upper mesa structure.

In one embodiment, a nanobeam cavity device includes an elongated waveguide having a central optical cavity, first and second lateral substrates that are positioned on opposed lateral sides of the waveguide, and carrier-injection beams that extend from the first and second lateral substrates to the central optical cavity of the elongated waveguide.