A surface emitting laser includes a first reflective layer, an active layer provided on the first reflective layer, and a second reflective layer provided on the active layer. The first reflective layer, the active layer, and the second reflective layer form a mesa, and the mesa has an electrically insulating region and an electrically conductive region. The electrically insulating region is positioned at a center portion of the mesa in a surface direction, and the electrically conductive region includes the first reflective layer, the active layer, and the second reflective layer and is positioned outside the electrically insulating region in such a manner as to surround the electrically insulating region.

An on-chip integrated semiconductor laser structure and a method for preparing the same. The structure includes: an epitaxial structure including a first N contact layer, a first N confinement layer, a first active region, a first P confinement layer, a first P contact layer, an isolation layer, a second N contact layer, a second N confinement layer, a second active region, a second P confinement layer, and a second P contact layer sequentially deposited on a substrate; a first waveguide and a second waveguide; a first optical grating and a second optical grating; and current injection windows.

A topological bulk laser includes a topological photonic crystal (32) having an energy band inversion between dipole mode and quadrupole mode near the center of Brillouin zone and a trivial photonic crystal (31) not having band inversion for splicing to each other. The reflection and confinement of an optical field occurs at the interface; and the interface encloses to form a closed contour, thereby forming a laser cavity with an effective cavity feedback for lasing at the interior of the interface. This band-inversion-induced reflection mechanism induces single-mode lasing with directional vertical emission. At room temperature, the topological bulk laser can achieve low threshold, narrow linewidth, and a high side-mode suppression ratio, reduce the fabrication difficulty and costs, and improve heat dissipation and electrical injection efficiency, hence improving lifetime and stability of devices.

A light-emitting device according to an embodiment of the present disclosure includes: a semiconductor stack in which a first light reflection layer configured by an arsenic-based semiconductor layer including carbon as an impurity, an active layer, and a second light reflection layer are stacked; a first buffer layer provided on the first light reflection layer side of the semiconductor stack, having one face that faces the semiconductor stack and another face that is on an opposite side of the one face, and configured by a phosphorus-based semiconductor layer; and a second buffer layer provided at least between the first light reflection layer and the first buffer layer, and configured by an arsenic-based semiconductor layer including zinc or magnesium as an impurity.

Various semiconductor laser and optical amplifier designs and injection current control methods are disclosed that enable tailoring a distribution of the injection current along an active waveguide of the laser or the optical amplifier. Such configurations can be used to reduce longitudinal current crowding along the active waveguide of the laser or the optical amplifier. The electrodes and/or one or more layers of the laser or the optical amplifier may be segmented to provide a tailored longitudinal injection current distribution.

An optoelectronic device includes a base chip, including a silicon die having a photodiode disposed at its front surface and a first anode contact and a first cathode contact disposed on the front surface. A laser diode driver circuit on the silicon die supplies an electrical drive signal between the first anode contact and the first cathode contact. An emitter chip includes a III-V semiconductor die, which is mounted with its front side facing toward the front surface of the silicon die. A second anode contact and a second cathode contact are disposed on the front side of the III-V semiconductor die in electrical communication with the first anode contact and the first cathode contact. A VCSEL is disposed on the front side of the III-V semiconductor die in coaxial alignment with the photodiode and receives the drive signal from the second anode contact and the second cathode contact.

[Object] To provide a compact and high-performance laser device and a laser apparatus.

[Solving Means] A laser device according to the present disclosure includes an excitation light source having a first reflective layer with respect to a first wavelength; a laser medium having a second reflective layer with respect to a second wavelength on a first surface facing to the excitation light source and a third reflective layer with respect to the first wavelength on a second surface opposite to the first surface; and a saturable absorber having a fourth reflective layer with respect to the second wavelength on a third surface opposite to the laser medium.

A light-emitting component includes a substrate, plural light-emitting elements that are disposed on the substrate and emit light in a direction intersecting with a surface of the substrate, and a gate electrode that is electrically connected to each of the plural light-emitting elements and that performs control so that the plural light-emitting elements are switched ON/OFF together. A distance between each of the plural light-emitting elements and the gate electrode is smaller than a largest distance between two light-emitting elements among the plural light-emitting elements.

Several VCSEL devices for long wavelength applications in wavelength range of 1200-1600 nm are described. These devices include an active region between a semiconductor DBR on a GaAs wafer and a dielectric DBR regrown on the active region. The active region includes multi-quantum layers (MQLs) confined between the active n-InP and p-InAlAs layers and a tunnel junction layer above the MQLs. The semiconductor DBR is fused to the bottom of the active region by a wafer bonding process. The design simplifies integrating the reflectors and the active region stack by having only one wafer bonding followed by regrowth of the other layers including the dielectric DBR. An air gap is fabricated either in an n-InP layer of the active region or in an air gap spacer layer on top of the semiconductor DBR. The air gap enhances optical confinement of the VCSEL. The air gap may also contain a grating.

A visible light source includes a substrate, a vertical-cavity surface-emitting laser including an active semiconductor region configured to emit infrared light and a first reflector configured to reflect the infrared light emitted by the active semiconductor region, a second reflector configured to reflect the infrared light and form a vertical cavity for the infrared light with the first reflector, and one or more micro-resonators configured to receive the infrared light and generate visible light in one or more colors using the infrared light through optical parametric oscillation. The visible light source also includes one or more output couplers configured to couple the visible light in one or more colors from the one or more micro-resonators into free space or into a photonic integrated circuit.