A method of manufacturing a semiconductor device, includes a step of forming, on a semiconductor substrate, a mesa stripe including an active layer, and a semiconductor layer covering the mesa stripe, a masking step of forming, on the semiconductor layer, a mask pattern through which the semiconductor layer is exposed on opposite sides of the mesa stripe, an isotropic etching step of performing isotropic etching on the semiconductor layer exposed through the mask pattern so that concaves having a circular-arc sectional shape are formed in the semiconductor layer, and an anisotropic etching step of performing anisotropic etching on the semiconductor layer through the mask pattern after the isotropic etching step so that etching progresses to the semiconductor substrate.

The mid-infrared laser system has an amplifier including at least one pump laser adapted to generate a pump laser beam and a length of fiber made of a low phonon energy glass and having at least one laser-active doped region between a first end and a second end, and a seed laser to generate a seed laser beam having a seed optical spectrum in the mid-infrared. The seed laser beam is launched into the first end to generate a mid-infrared laser beam outputted from the second end via stimulated emission upon pumping of the at least one laser-active doped region with the pump laser beam. When the power of the pump laser exceeds a spectrum modification threshold, the mid-infrared laser beam has an output optical spectrum being broadened relative to the seed optical spectrum.

A light emitting component includes plural transfer elements, plural setting thyristors, and plural light emitting elements. The transfer elements are configured to be sequentially brought into an ON state. The setting thyristors are connected to the transfer elements, respectively. The setting thyristors are configured to be brought into a state where the setting thyristors are capable of changing to the ON state when the transfer elements are brought into the ON state. The light emitting elements are stacked on the setting thyristors through tunnel junctions, respectively. The light emitting elements are configured to emit light of increase a light emission amount when the setting thyristors are brought into the ON state.

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; a separate confinement heterostructure layer positioned between the quantum well active layer and the n-type cladding layer; and 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.

Embodiments of the present disclosure may relate to a hybrid silicon distributed feed-back (DFB) laser, wherein light is to propagate through the DFB laser along a length of the DFB laser. The DFB laser may include a mesa with a current channel that extends from the first side of the mesa to the second side of the mesa. At a first location along the length of the DFB laser, the current channel may have a first width and/or the mesa may have a second width. At a second location along the length of the DFB laser, the current channel may have a third width and/or the mesa may have a fourth width as measured in a direction perpendicular to the length of the DFB laser. Other embodiments may be described and/or claimed.

Embodiments of the present disclosure may relate to a hybrid silicon distributed feed-back (DFB) laser, wherein light is to propagate through the DFB laser along a length of the DFB laser. The DFB laser may include a mesa with a current channel that extends from the first side of the mesa to the second side of the mesa. At a first location along the length of the DFB laser, the current channel may have a first width and/or the mesa may have a second width. At a second location along the length of the DFB laser, the current channel may have a third width and/or the mesa may have a fourth width as measured in a direction perpendicular to the length of the DFB laser. Other embodiments may be described and/or claimed.

In a semiconductor laser, a block layer is provided on both sides of a mesa-type semiconductor part having an n-type cladding layer, an active layer, and a p-type cladding layer. The block layer has: a p-type block layer formed on the side surface of the mesa-type semiconductor part and over a p-type semiconductor substrate; a high-resistance layer formed over the p-type block layer; and an n-type block layer formed over the high-resistance layer, which has a higher resistance than that of the p-type block layer. By providing the high-resistance layer between the p-type block layer and the n-type block layer, the thickness of the p-type block layer can be controlled and a leakage current (flow of a hole) can be reduced. Further, the distance between the n-type cladding layer and the n-type block layer can be secured, and hence a leakage current (flow of an electron) can be prevented.

The mid-infrared laser system has an amplifier including at least one pump laser adapted to generate a pump laser beam and a length of fiber made of a low phonon energy glass and having at least one laser-active doped region between a first end and a second end, and a seed laser to generate a seed laser beam having a seed optical spectrum in the mid-infrared. The seed laser beam is launched into the first end to generate a mid-infrared laser beam outputted from the second end via stimulated emission upon pumping of the at least one laser-active doped region with the pump laser beam. When the power of the pump laser exceeds a spectrum modification threshold, the mid-infrared laser beam has an output optical spectrum being broadened relative to the seed optical spectrum.

A semiconductor laser device includes: a ridge having an n-type clad layer, a lower-side light confinement layer, an active layer, and an upper-side light confinement layer which are laminated in this order from a lower side; current blocking layers embedded on both sides of the ridge, the current blocking layers each having a semi-insulating blocking layer covering a side surface of the ridge, an intermediate blocking layer, and an n-type blocking layer which are laminated in this order from the lower side; and a p-type clad layer formed on the ridge and the current blocking layers, in which the ridge has the upper-side light confinement layer as an uppermost layer of the ridge, and the intermediate blocking layer has a higher energy level at a bottom of a conduction band of the intermediate blocking layer compared to the semi-insulating blocking layer.

A laser diode has a layer arrangement including a first layer structure extending along a Z axis in a longitudinal direction, along an X axis in a transverse direction and along a Y axis in a height direction, and a second and third layer structure arranged along the Z axis on opposite longitudinal sides of the first layer structure and adjoining the first layer structure, wherein the active zone of the first layer structure is arranged offset in height relative to the active zones of the second and third layer structures, and an intermediate layer is arranged laterally with respect to the first layer structure in the second and third layer structures, the intermediate layer configured as an electrically blocking layer that hinders or prevents a current flow, and the intermediate layer being arranged between the active zone and an n contact.