Abstract: A submount includes a light emitting device mounted thereon. The submount includes: a base including a first surface extending in a first direction and in a second direction that is orthogonal to the first direction; a first electrode extending in the first direction and in the second direction on the first surface, the first electrode including a first end in the second direction, and a second end in opposite direction of the second direction, the second end extending in the first direction; and a second electrode extending in the first direction and in the second direction on the first surface, the second electrode including a third end in the opposite direction of the second direction, the third end being separated from the first end in the second direction with a gap therebetween, and a fourth end in the second direction, the fourth end extending in the first direction.

Abstract: A semiconductor laser device of an edge emission type, where a waveguide mode is multi-mode, is provided. The semiconductor laser device includes a first facet of the waveguide on an emission direction front side, the first facet having a first width in a horizontal direction perpendicular to a longitudinal direction of the waveguide; and a second facet of the waveguide on an emission direction rear side, the second facet having the first width, wherein a width of the waveguide, in the horizontal direction, is at least partially narrower than the first width, between the first facet and the second facet.

Abstract: A semiconductor-laser-chip-on-submount includes: a semiconductor laser chip that includes a semiconductor portion having an emitting facet and a rear facet along a longitudinal direction and emits laser light from the emitting facet; and a submount where the semiconductor laser chip is mounted. Further, a first distance between the submount and the emitting facet of the semiconductor portion is less than a second distance between the submount and the rear facet of the semiconductor portion.

Abstract: A semiconductor laser device of an edge emission type, where a waveguide mode is multi-mode, is provided. The semiconductor laser device includes a first facet of the waveguide on an emission direction front side, the first facet having a first width in a horizontal direction perpendicular to a longitudinal direction of the waveguide; and a second facet of the waveguide on an emission direction rear side, the second facet having the first width, wherein a width of the waveguide, in the horizontal direction, is at least partially narrower than the first width, between the first facet and the second facet.

Abstract: A semiconductor laser device of an edge emission type, where a waveguide mode is multi-mode, is provided. The semiconductor laser device includes a first facet of the waveguide on an emission direction front side, the first facet having a first width in a horizontal direction perpendicular to a longitudinal direction of the waveguide; and a second facet of the waveguide on an emission direction rear side, the second facet having the first width, wherein a width of the waveguide, in the horizontal direction, is at least partially narrower than the first width, between the first facet and the second facet.

Abstract: A semiconductor device includes a semiconductor layer formed of a III-V group semiconductor crystal containing As as a primary component of a V group. A V group element other than As has been introduced at a concentration of 0.02 to 5% into a V group site of the III-V group semiconductor crystal in the semiconductor layer.

Abstract: A semiconductor device includes a semiconductor layer formed of a III-V group semiconductor crystal containing As as a primary component of a V group. A V group element other than As has been introduced at a concentration of 0.02 to 5% into a V group site of the III-V group semiconductor crystal in the semiconductor layer.

Abstract: A semiconductor laser device includes an active layer including a well layer and a barrier layer formed of a III-V group semiconductor crystal containing As as a primary component of a V group. A V group element other than As has been introduced at a concentration of 0.02 to 5% into a V group site of the III-V group semiconductor crystal in at least one of the well layer and the barrier layer, and a III group site of the III-V group semiconductor crystal in at least one of the well layer and the barrier layer contains Al.