The light-emitting element of an embodiment outputs a clear optical image while suppressing light output efficiency reduction, and includes a substrate, a light-emitting unit, and a bonding layer. The light-emitting unit has a semiconductor stack, including a phase modulation layer, between first and second electrodes. The phase modulation layer has a base layer and modified refractive index regions, and includes a first region having a size including the second electrode, and a second region. Each gravity center of the second region's modified refractive index region is arranged by an array condition. The light from the stack is a single beam, and regarding a first distance from the substrate to the stack's front surface and a second distance from the substrate to the stack's back surface, a variation amount of the first distance along a direction on the substrate is smaller than a variation amount of the second distance.

A light emitting device includes a substrate, a laminated structure which is provided to the substrate, and includes a light emitting layer, a first electrode which has contact with the laminated structure at an opposite side of the laminated structure to the substrate, and is configured to inject an electrical current into the light emitting layer, and a wiring layer which is electrically coupled to the first electrode, and has a light shielding property with respect to light generated in the light emitting layer, wherein the wiring layer is provided with a first opening part which the light emitted from the laminated structure passes through, and the first opening part is located inside an outer edge of the first electrode in a plan view.

A control circuit in this laser equipment drives a drive circuit of a photonic crystal laser element under a predetermined condition. It was found that a wavelength width of a laser beam to be output from the photonic crystal laser element is dependent on a standardized drive current k and a pulse width T, and had a predetermined relationship with these. By meeting this condition, a laser beam with a plurality of wavelengths can be controlled and output.

A laser structure comprising a first photonic crystal surface emitting laser (PCSEL), a second PCSEL, and a coupling region that extends between the first PCSEL and the second PCSEL along a longitudinal axis and that is electrically controllable so as to be capable of coherently coupling the first PCSEL to the second PCSEL. Each PCSEL include an active layer, a photonic crystal, and a two-dimensional periodic array distributed in an array plane parallel to the longitudinal axis within the photonic crystal where the two-dimensional periodic array is formed of regions having a refractive index that is different to the surrounding photonic crystal.

A surface emitting quantum cascade laser includes an active layer, a first semiconductor layer, and first electrode. The active layer has a plurality of quantum well layers stacked therein. The active layer is capable of emitting laser light by inter-subband transition. The first semiconductor layer is provided on the active layer and having a first surface provided with a plurality of pits so as to constitute a two-dimensional lattice. The first electrode is provided on the first semiconductor layer and having a periodic opening. Each pit is asymmetric with respect to a line parallel to a side of the lattice. The laser light is emitted in a direction generally perpendicular to the active layer from a pit exposed to the opening.

A two-dimensional photonic crystal surface emitting laser capable of improving characteristics of light to be emitted, particularly optical output , which includes: a two-dimensional photonic crystal including a plate-shaped base member and modified refractive index regions where the modified refractive index regions have a refractive index different from that of the plate-shaped base member and are two-dimensionally and periodically arranged in the base member; an active layer provided on one side of the two-dimensional photonic crystal; and a first electrode and a second electrode provided sandwiching the two-dimensional photonic crystal and the active layer for supplying current to the active layer, where the second electrode covers a region equal to or wider than the first electrode, wherein the first electrode is formed so as to supply the current to the active layer with a different density depending on the in-plane position on the first electrode.

Provided is a biosensor. The biosensor includes a substrate, an optical structure provided on the substrate, and a cover provided on the substrate and having a bridge shape that is in contact with a top surface of the substrate at both sides of the optical structure. The cover has a channel extending in a first direction, the optical structure is provided inside the channel, and the optical structure is configured to capture biomaterials that travel through the channel.

A light emitting apparatus according to an aspect of the present disclosure includes a substrate, a columnar section group including a plurality of columnar sections each having a laminated structure of a first semiconductor layer, a light emitting layer, and a second semiconductor layer, and an electrode via which electric current is injected into the plurality of columnar sections. The plurality of columnar sections include a plurality of first columnar sections and a plurality of second columnar sections disposed around the plurality of first columnar sections. The second columnar sections each have the shape of each of the first columnar sections except that part of the shape is missing. The second columnar sections are lower than the first columnar sections. The electrode is electrically insulated from the plurality of second columnar sections.

A light emitting device includes a substrate, and a stacked body provided to the substrate, and including a plurality of first columnar parts, wherein the stacked body includes a first semiconductor layer, a second semiconductor layer different in conductivity type from the first semiconductor layer, and a light emitting layer disposed between the first semiconductor layer and the second semiconductor layer, the first semiconductor layer and the light emitting layer constitute the first columnar parts, the first semiconductor layer is disposed between the substrate and the light emitting layer, the second semiconductor layer is provided with a plurality of recessed parts, the recessed part is provided with a low refractive-index part lower in refractive index than the second semiconductor layer, a plurality of the first columnar parts constitutes a first photonic crystal, the second semiconductor layer and the low refractive-index parts constitute a second photonic crystal, and the first photonic crystal and the second photonic crystal are optically coupled to each other.

According to one embodiment, a surface-emitting quantum cascade laser includes a substrate; a mesa portion of a semiconductor stacked body located on the substrate, and a reflective film located at a sidewall of the mesa portion. The mesa portion includes a light-emitting layer emitting light due to an intersubband transition of a carrier, and a photonic crystal layer including a two-dimensional diffraction grating.