An optical device has a gallium and nitrogen containing substrate including a surface region and a strain control region, the strain control region being configured to maintain a quantum well region within a predetermined strain state. The device also has a plurality of quantum well regions overlying the strain control region.

A semiconductor laser device includes a first cladding including gallium nitride (GaN) on a substrate, a light waveguide on the first cladding, a first contact pattern, a first SCH pattern, a first active pattern, a second SCH pattern, a second cladding and a second contact pattern sequentially stacked on the light waveguide, and first and second electrodes on the first and second contact patterns, respectively.

An edge-emitting semiconductor laser diode chip 15 with mutually opposed front and back end facet mirrors 22, 24. First and second ridges 26.sub.1, 26.sub.2 extend between the chip end facets 22, 24 to define first and second waveguides in an active region layer. Low and high slope efficiency laser diodes are thus formed that are independently drivable by respective electrode pairs 21.sub.1, 23.sub.1 and 21.sub.2, 23.sub.2. The single chip 15 thus incorporates two laser diodes sharing a common heterostructure, one with low slope efficiency optimized for low power operation with good power stability against temperature variations and random threshold current fluctuations in the close-to-threshold power regime, and the other with high slope efficiency optimized for high wall plug efficiency operation at higher output powers when the chip is operating far above threshold.

There is provided a semiconductor laser including: a first mirror layer; a second mirror layer; an active layer; a current confinement layer; a first region including a plurality of first oxidized layers; and a second region including a plurality of second oxidized layers, in which, in a plan view, the laminated body includes a first part including the first region and the second region, a second part including the first region and the second region, and a third part disposed between the first part and the second part and resonating light generated in the active layer, the third part includes a fourth part including the first region and the second region and having a first groove, a fifth part including the first region and the second region and having a second groove, and a sixth part disposed between the fourth part and the fifth part and sandwiched between the first part and the second part, in a plan view.

Provided is a nitride semiconductor element that does not cause element breakdown even when driven at high current density. A nitride semiconductor element includes an active layer, an electron block layer formed above the active layer, an AlGaN layer formed on the electron block layer, and a cover layer covering an upper surface of the AlGaN layer and formed of AlGaN or GaN having a lower Al composition ratio than in the AlGaN layer, in which the AlGaN layer includes protrusions provided on a surface opposite to the active layer, and the cover layer covers the protrusions. The AlGaN layer is preferably formed of AlGaN having an Al composition ratio decreasing in a direction away from the active layer, and the protrusions preferably have a frustum shape.

A laser structure, including: a dielectric matrix formed of a first material; a laser source formed within the dielectric matrix and formed of a semiconductor material; and a plurality of side confining features formed within the dielectric matrix and extending parallel to and along a length of the laser source. The plurality of side confining features are formed of the semiconductor material.

A laser device includes a first waveguiding layer, an active layer, a second waveguiding layer, a contact layer, a first insulating layer, a plurality of hole fillings, a first electrode, and a second electrode. The first waveguiding layer, the active layer, the second waveguiding layer, and the contact layer are stacked in sequence to form an epitaxy structure. The epitaxy structure has a first platform, the first platform has multiple holes to form a photonic crystal structure. The first insulating layer is over an upper surface and a sidewall surface of the first platform, wherein the first insulating layer has a first aperture corresponding to the photonic crystal structure. The hole fillings are respectively filled in the holes. The first electrode is over the photonic crystal structure. The second electrode is electrically connected to the first waveguiding layer.

An optical module includes a waveguide interposer and at least one light source unit. The waveguide interposer includes at least one input terminal, at least one waveguide channel, and at least one output terminal. The at least one input terminal is configured to receive laser light, and the at least one waveguide channel is coupled to the at least one input terminal and is configured to guide the laser light. Each light source unit is configured to output the laser light to a corresponding input terminal of the at least one input terminal.

A laser structure, including: a dielectric matrix formed of a first material; a laser source formed within the dielectric matrix and formed of a semiconductor material; and a plurality of side confining features formed within the dielectric matrix and extending parallel to and along a length of the laser source. The plurality of side confining features are formed of the semiconductor material.

A laser structure, including: a dielectric matrix formed of a first material; a laser source formed within the dielectric matrix and formed of a semiconductor material; and a plurality of side confining features formed within the dielectric matrix and extending parallel to and along a length of the laser source. The plurality of side confining features are formed of the semiconductor material.