Abstract: A surface-emitting laser according to one embodiment of the technology includes a laser element section that includes a first multi-layer film reflecting mirror, a first semiconductor layer of a first conductivity type, an active layer, a second semiconductor layer of a second conductivity type, a second multi-layer film reflecting mirror, a nitride semiconductor layer of the second conductivity type, and a light output surface in this order. The laser element section further includes an electrode that injects a current into the active layer.

Abstract: A light emitting element includes at least a first light reflecting layer formed on a surface of a substrate, a laminated structural body made of a first compound semiconductor layer, an active layer and a second compound semiconductor layer formed on the first light reflecting layer, and a second electrode and a second light reflecting layer formed on the second compound semiconductor layer, the laminated structural body is configured from a plurality of laminated structural body units, a light emitting element unit is configured from each of the laminated structural body units, and a resonator length in the light emitting element unit is different in every light emitting element unit.

Abstract: Provided is an optical semiconductor device including a laminate structural body 20 in which an n-type compound semiconductor layer 21, an active layer 23, and a p-type compound semiconductor layer 22 are laminated in this order. The active layer 23 includes a multiquantum well structure including a tunnel barrier layer 33, and a compositional variation of a well layer 312 adjacent to the p-type compound semiconductor layer 22 is greater than a compositional variation of another well layer 311. Band gap energy of the well layer 312 adjacent to the p-type compound semiconductor layer 22 is smaller than band gap energy of the other well layer 311. A thickness of the well layer 312 adjacent to the p-type compound semiconductor layer 22 is greater than a thickness of the other well layer 311.

Abstract: A semiconductor optical device has a multilayer structure 30 including a first compound semiconductor layer 31, an active layer 33, and a second compound semiconductor layer 32. A second electrode 42 is formed on the second compound semiconductor layer 32 through a contact layer 34. The contact layer 34 has a thickness of four or less atomic layers. When an interface between the contact layer 34 and the second compound semiconductor layer 32 is an xy-plane, a lattice constant along an x-axis of crystals constituting an interface layer 32A which is a part of the second compound semiconductor layer in contact with the contact layer 34 is x2, a lattice constant along a z-axis is z2, a length along an x-axis in one unit of crystals constituting the contact layer 34 is xc?, and a length along the z-axis is zc?, (zc?/xc?)>(z2/x2) is satisfied.

Abstract: A light-emitting element includes at least a GaN substrate 11; a first light reflecting layer 41 formed on the GaN substrate 11 and functioning as a selective growth mask layer 44; a first compound semiconductor layer 21, an active layer 23, and a second compound semiconductor layer 22 that are formed on the first light reflecting layer; and a second electrode 32 and a second light reflecting layer 42 that are formed on the second compound semiconductor layer 22. An off angle of the plane orientation of the surface of the GaN substrate 11 is 0.4 degrees or less, the area of the first light reflecting layer 41 is 0.8S0 or less, where S0 represents the area of the GaN substrate 11, and as a bottom layer 41A of the first light reflecting layer, a thermal expansion relaxation film 44 is formed on the GaN substrate 11.

Abstract: Provided is an optical semiconductor element including: a stacked structure body 20 formed of a first compound semiconductor layer 21, a third compound semiconductor layer (active layer) 23, and a second compound semiconductor layer 22. A fundamental mode waveguide region 40 with a waveguide width W1, a free propagation region 50 with a width larger than W1, and a light emitting region 60 having a tapered shape (flared shape) with a width increasing toward a light emitting end surface 25 are arranged in sequence.

Abstract: Provided is an optical semiconductor device including a laminate structural body 20 in which an n-type compound semiconductor layer 21, an active layer 23, and a p-type compound semiconductor layer 22 are laminated in this order. The active layer 23 includes a multiquantum well structure including a tunnel barrier layer 33, and a compositional variation of a well layer 312 adjacent to the p-type compound semiconductor layer 22 is greater than a compositional variation of another well layer 311. Band gap energy of the well layer 312 adjacent to the p-type compound semiconductor layer 22 is smaller than band gap energy of the other well layer 311. A thickness of the well layer 312 adjacent to the p-type compound semiconductor layer 22 is greater than a thickness of the other well layer 311.

Abstract: A surface-emitting laser according to one embodiment of the technology includes a laser element section that includes a first multi-layer film reflecting mirror, a first semiconductor layer of a first conductivity type, an active layer, a second semiconductor layer of a second conductivity type, a second multi-layer film reflecting mirror, a nitride semiconductor layer of the second conductivity type, and a light output surface in this order. The laser element section further includes an electrode that injects a current into the active layer.

Abstract: A light emitting element includes at least a first light reflecting layer formed on a surface of a substrate, a laminated structural body made of a first compound semiconductor layer, an active layer and a second compound semiconductor layer formed on the first light reflecting layer, and a second electrode and a second light reflecting layer formed on the second compound semiconductor layer, the laminated structural body is configured from a plurality of laminated structural body units, a light emitting element unit is configured from each of the laminated structural body units, and a resonator length in the light emitting element unit is different in every light emitting element unit.

Abstract: A semiconductor optical device has a multilayer structure 30 including a first compound semiconductor layer 31, an active layer 33, and a second compound semiconductor layer 32. A second electrode 42 is formed on the second compound semiconductor layer 32 through a contact layer 34. The contact layer 34 has a thickness of four or less atomic layers. When an interface between the contact layer 34 and the second compound semiconductor layer 32 is an xy-plane, a lattice constant along an x-axis of crystals constituting an interface layer 32A which is a part of the second compound semiconductor layer in contact with the contact layer 34 is x2, a lattice constant along a z-axis is z2, a length along an x-axis in one unit of crystals constituting the contact layer 34 is xc?, and a length along the z-axis is zc?, (zc?/xc?)>(z2/x2) is satisfied.

Abstract: A method of manufacturing a light emitting element includes, sequentially (a) forming a first light reflecting layer having a convex shape; (b) forming a layered structure body by layering a first compound semiconductor layer, an active layer, and a second compound semiconductor layer; (c) forming, on the second surface of the second compound semiconductor layer, a second electrode and a second light reflecting layer formed from a multilayer film; (d) fixing the second light reflecting layer to a support substrate; (e) removing the substrate for manufacturing a light emitting element, and exposing the first surface of the first compound semiconductor layer and the first light reflecting layer; (f) etching the first surface of the first compound semiconductor layer; and (g) forming a first electrode on at least the etched first surface of the first compound semiconductor layer.

Abstract: A semiconductor optical device has a multilayer structure 30 including a first compound semiconductor layer 31, an active layer 33, and a second compound semiconductor layer 32. A second electrode 42 is formed on the second compound semiconductor layer 32 through a contact layer 34. The contact layer 34 has a thickness of four or less atomic layers. When an interface between the contact layer 34 and the second compound semiconductor layer 32 is an xy-plane, a lattice constant along an x-axis of crystals constituting an interface layer 32A which is a part of the second compound semiconductor layer in contact with the contact layer 34 is x2, a lattice constant along a z-axis is z2, a length along an x-axis in one unit of crystals constituting the contact layer 34 is xc?, and a length along the z-axis is zc?, (zc?/xc?)>(z2/x2) is satisfied.

Abstract: A multi-junction solar cell that is lattice-matched with a base, and that includes a sub-cell having a desirable band gap is provided. A plurality of sub-cells are laminated, each including first and second compound semiconductor layers. At least one predetermined sub-cell is configured of first layers and a second layer. In each of the first layers, a 1-A layer and a 1-B layer are laminated. In the second layer, a 2-A layer and a 2-B layer are laminated. A composition A of the 1-A layer and the 2-A layer is determined based on a value of a band gap of the predetermined sub-cell. A composition B of the 1-B layer and the 2-B layer is determined based on a difference between a base lattice constant of the base and a lattice constant of the composition A. Thicknesses of 1-B layer and 2-B layer are determined based on difference between base lattice constant and a lattice constant of composition B, and on thickness of the 1-A layer and thickness of 2-A layer.

Abstract: A semiconductor laser apparatus is provided. The semiconductor laser apparatus includes a mode-locked semiconductor laser device and an external resonator including a dispersion compensation system, wherein the semiconductor laser apparatus is configured to generate self modulation, to introduce a negative group velocity dispersion into the external resonator, and to provide spectral filtering after the external resonator.

Abstract: A method of manufacturing a light emitting element includes, sequentially (a) forming a first light reflecting layer having a convex shape; (b) forming a layered structure body by layering a first compound semiconductor layer, an active layer, and a second compound semiconductor layer; (c) forming, on the second surface of the second compound semiconductor layer, a second electrode and a second light reflecting layer formed from a multilayer film; (d) fixing the second light reflecting layer to a support substrate; (e) removing the substrate for manufacturing a light emitting element, and exposing the first surface of the first compound semiconductor layer and the first light reflecting layer; (f) etching the first surface of the first compound semiconductor layer; and (g) forming a first electrode on at least the etched first surface of the first compound semiconductor layer.

Abstract: A light emitting element includes at least a first light reflecting layer 41 formed on a surface of a substrate 11, a laminated structural body 20 made of a first compound semiconductor layer 21, an active layer 23 and a second compound semiconductor layer 22 formed on the first light reflecting layer 41, and a second electrode 32 and a second light reflecting layer 42 formed on the second compound semiconductor layer 22, the laminated structural body 20 is configured from a plurality of laminated structural body units 20A, a light emitting element unit 10A is configured from each of the laminated structural body units 20A, and a resonator length in the light emitting element unit 10A is different in every light emitting element unit.

Abstract: A light emitting device, includes a selective growth mask layer 44; a first light reflection layer 41 thinner than the selective growth mask layer 44; a laminated structure including a first compound semiconductor layer 21, an active layer 23, and a second compound semiconductor layer 22, the first compound semiconductor layer 21 being formed on the first light reflection layer 41; and a second electrode 32 formed on the second compound semiconductor layer 22, and a second light reflection layer 42, in which the second light reflection layer 42 is opposed to the first light reflection layer 41, and the second light reflection layer is not formed on an upper side of the selective growth mask layer 44.

Abstract: Provided is an optical semiconductor device including a laminate structural body 20 in which an n-type compound semiconductor layer 21, an active layer 23, and a p-type compound semiconductor layer 22 are laminated in this order. The active layer 23 includes a multiquantum well structure including a tunnel barrier layer 33, and a compositional variation of a well layer 312 adjacent to the p-type compound semiconductor layer 22 is greater than a compositional variation of another well layer 311. Band gap energy of the well layer 312 adjacent to the p-type compound semiconductor layer 22 is smaller than band gap energy of the other well layer 311. A thickness of the well layer 312 adjacent to the p-type compound semiconductor layer 22 is greater than a thickness of the other well layer 311.

Abstract: A semiconductor laser element includes a stacked structure body, a second electrode 62, and a first electrode 61; a ridge stripe structure 71 formed of at least part of the stacked structure body is formed; a side structure body 72 formed of the stacked structure body is formed on both sides of the ridge stripe structure 71; the second electrode 62 is separated into a first portion for sending a direct current to the first electrode via a light emitting region and a second portion 62B for applying an electric field to a saturable absorption region; a protection electrode 81 is formed on a portion adjacent to the second portion 62B of the second electrode of at least one side structure body 72; and an insulating layer 56 made of an oxide insulating material is formed to extend from on a portion of the ridge stripe structure 71 to on a portion of the side structure body 72, on which portions neither the second electrode nor the protection electrode 81 is formed.

Abstract: A semiconductor-laser-device assembly includes a mode-locked semiconductor-laser-element assembly including a mode-locked semiconductor laser element, and a dispersion compensation optical system, on which laser light emitted from the mode-locked semiconductor laser element is incident and from which the laser light is emitted; and a semiconductor optical amplifier having a layered structure body including a group III-V nitride-based semiconductor layer, the semiconductor optical amplifier configured to amplify the laser light emitted from the mode-locked semiconductor-laser-element assembly.