Kabushiki Kaisha Toshiba

National Institute for Materials Science

Tsutomu Kakuno

Shinji Saito

Hiroshi Ohno

Rei Hashimoto

Kei Kaneko

Tomohiro Takase

Yuichiro Yamamoto

Yasunobu Kai

Yasutomo Shiomi

Osamu Yamane

Hiroshi Hasegawa

Akira Tsumura

Shigeyuki Takagi

Akira Maekawa

Miyuki Kusaba

Hiroshi Ito

Naotada Okada

Hiroki Iwanaga

Masatoshi Hirono

Shigeki Matsunaka

Toshitake Kitagawa

Naoki Ikeda

Ryuichi Togawa

Takashi Magara

Atsushi Fujihara

Isao Muraoka

Yoshimasa Sugimoto

Kazuaki Sakoda

Takashi Kuroda

The present embodiment provides a composition containing a rare earth complex and a fluorine-based solvent, which can also be used in a fluorescent flaw inspection method. A rare earth complex-containing composition according to the present embodiment is a rare earth complex-containing composition that contains a rare earth complex containing: a rare earth ion; two or more phosphine oxide ligands having different structures; and a β-diketone ligand, the rare earth complex being dissolved in a fluorine-based solvent. The present embodiment also relates to a fluorescent flaw inspection method using the same.

Rare earth complex-containing composition and fluorescent penetrant inspection method using same

A gas detection device according to an embodiment includes a first irradiation part configured to irradiate a first light having a first wavelength on a gas released into a space, a second irradiation part configured to irradiate, on the gas, a second light having a second wavelength that is less than the first wavelength, an irradiation position adjustment part configured to control an irradiation position of the first light on the gas, a gas analysis part configured to analyze a component of the gas based on the first light having passed through the gas, and a gas visualization part configured to visualize a concentration distribution of the gas based on the second light having passed through the gas. The irradiation position adjustment part controls the irradiation position of the first light on the gas based on the visualized concentration distribution of the gas.

Gas detection device and gas detection method

A gas detection device according to an embodiment includes a first light source irradiating infrared, a second light source irradiating visible light, a low-pass filter that transmits the infrared irradiated from the first light source, reflects the visible light irradiated from the second light source, and aligns an optical axis of the visible light with an optical axis of the infrared, a first retroreflector on which the infrared and the visible light having the aligned optical axes are incident, a first detecting part detecting the infrared reflected by the first retroreflector, and a scattering body located at a center of the first retroreflector.

Gas detection device

A quantum cascade laser includes light-emitting quantum well layers configured to emit infrared laser light by an intersubband transition; and injection quantum well layers configured to relax carrier energy. The light-emitting quantum well layers and the injection quantum well layers are stacked alternately. The injection quantum well layers relax the energy of carriers injected from the light-emitting quantum well layers, respectively. The light-emitting quantum well layers and the injection quantum well layers including barrier layers. At least one barrier layer includes first and second regions of a first ternary compound semiconductor, and a binary compound semiconductor thin film. The binary compound semiconductor thin film is provided between the first and second regions. The first ternary compound semiconductor includes Group III atoms and a Group V atom. The binary compound semiconductor thin film includes one Group III atom of the first ternary compound semiconductor and the Group V atom.

Quantum cascade laser and method for manufacturing same

A surface-emitting semiconductor light-emitting device includes a first semiconductor layers, an active layer on the first semiconductor layer, a photonic crystal layer on the active layer and a second semiconductor layer on the photonic crystal layer. The photonic crystal layer include first protrusions in a first region and second protrusions in a second region. A spacing of adjacent first protrusions is greater than a spacing of adjacent second protrusions. The second semiconductor layer includes a first layer and a second layer on the first layer. The first layer covers first and second protrusions so that a first space remains between the adjacent first protrusions. The first layer includes a first portion provided between the adjacent second protrusions. The second layer includes a second portion provided between the adjacent first protrusions. The first space between the adjacent first protrusions is filled with the second portion of the second layer.

Surface-emitting semiconductor light-emitting device

According to one embodiment, a gas analysis device includes: a base including a concave portion; a window includes a first film and a second film; an optical part that is located at a side of the window opposite to the base side and includes a light projector and a light receiver; and an optical path length controller that is located between the base and the window and has a controllable thickness. The concave portion includes a first sidewall that is oblique to a surface of the base, and a second sidewall that is oblique to the surface of the base. An oblique direction of the second sidewall is opposite to an oblique direction of the first sidewall. The light projector is configured to irradiate light toward the first sidewall. The light receiver is configured to convert light reflected by the second sidewall.

Gas analysis device

A quantum cascade laser has an active layer, a first and second cladding layer, and an optical guide layer. The active layer has a plurality of injection quantum well regions and a plurality of light-emitting quantum well regions. The each of the injection quantum well regions and the each of the light-emitting quantum well regions are alternatively stacked. The first and second cladding layers are provided to interpose the active layer from both sides, and have a refractive index lower than an effective refractive index of the each of the light-emitting quantum well regions. The optical guide layer is disposed to divide the active layer into two parts. The optical guide layer has a refractive index higher than the effective refractive index of the each of the light-emitting quantum well regions, and has a thickness greater than the thickness of all well layers of quantum well layers.

Quantum cascade laser

A quantum cascade laser of an embodiment includes a semiconductor stacked body in which a ridge waveguide is provided. The semiconductor stacked body includes an active layer including a quantum well region including a layer including Al; and the active layer emits laser light. The layer that includes Al includes first regions, and a second region interposed between the first regions; the first region includes Al oxide and reaches a prescribed depth inward from an outer edge of the active layer along a direction parallel to a surface of the active layer in a cross section orthogonal to the optical axis; and the second region does not include Al oxide.

A semiconductor laser wafer includes a substrate, a first semiconductor layer, an active layer, a second semiconductor layer, and a composition evaluation layer. The active layer is provided on the first semiconductor layer; multiple periods of pairs of a light-emitting multi-quantum well region and an injection multi-quantum well region are stacked in the active layer; the light-emitting multi-quantum well region is made of a first compound semiconductor and a second compound semiconductor. The second semiconductor layer is provided on the active layer. The composition evaluation layer is provided above the active layer and includes a first film and a second film; the first film is made of the first compound semiconductor and has a first thickness; and the second film is made of the second compound semiconductor and has a second thickness.

Semiconductor laser wafer and semiconductor laser

A distributed feedback semiconductor laser of includes a semiconductor stacked body and a first electrode. The semiconductor stacked body includes a first layer, an active layer that is provided on the first layer and is configured to emit laser light by an intersubband optical transition, and a second layer that is provided on the active layer. The semiconductor stacked body has a first surface including a flat portion and a trench portion; the flat portion includes a front surface of the second layer; the trench portion reaches the first layer from the front surface; the flat portion includes a first region and a second region; the first region extends along a first straight line; the second region extends to be orthogonal to the first straight line; and the trench portion and the second region outside the first region form a diffraction grating having a prescribed pitch along the first straight line. The first electrode is provided in the first region.

Distributed feedback semiconductor laser

A surface emitting quantum cascade laser includes an active layer and a first semiconductor layer. The active layer includes a plurality of quantum well layers and is capable of emitting laser light by intersubband transition. The first surface includes an internal region and an outer peripheral region. Grating pitch of the first pits is m times grating pitch of the second pits. The outer peripheral region surrounds the internal region. A first planar shape of an opening end of the first pit is asymmetric with respect to a line passing through barycenter of the first planar shape and is parallel to at least one side of the first two-dimensional grating. A second planar shape of an opening end of the second pit is symmetric with respect to each of lines passing through barycenter of the second planar shape and is parallel to either side of the second two-dimensional grating.

Surface emitting quantum cascade laser

A substrate including a photonic crystal has a compound semiconductor, dielectric layers, and a first semiconductor layer. The dielectric layers are provided on a surface of the compound semiconductor substrate and disposed at each grating point of a two-dimensional diffraction grating, each of the dielectric layers having an asymmetric shape in relation to at least one edge of the two-dimensional diffraction grating and having a refractive index lower than a refractive index of the compound semiconductor substrate. The first semiconductor layer includes a flat first face covering the dielectric layers and the surface of the compound semiconductor substrate, a layer constituting the first face containing a material capable of being lattice matched to a material constituting the compound semiconductor substrate.

Substrate including photonic crystal and method for manufacturing the same, and surface emitting quantum cascade laser

A surface-emitting quantum cascade laser of an embodiment comprises a substrate, an active layer, and a photonic crystal layer. The active layer has optical nonlinearity, and is capable of emitting a first and a second infrared laser light. The photonic crystal layer includes a first and a second region. The rectangular grating of the first region is orthogonal to the rectangular grating of the second region. The first infrared laser light has a wavelength corresponding to a maximum gain outside a first photonic bandgap in a direction parallel to a first side of two sides constituting the rectangular grating. The second infrared laser light has a wavelength corresponding to a maximum gain outside a second photonic bandgap in a direction parallel to a second side of the two sides of the rectangular grating.

Surface-emitting quantum cascade laser

A surface-emitting quantum cascade laser of an embodiment includes a semiconductor stacked body, an upper electrode, and a lower electrode. The semiconductor stacked body includes an active layer that includes a quantum well layer and emits infrared laser light, a first semiconductor layer that includes a photonic crystal layer in which pit parts constitute a rectangular grating, and a second semiconductor layer. The upper electrode is provided on the first semiconductor layer. The lower electrode is provided on a lower surface of a region of the second semiconductor layer overlapping at least the upper electrode. The photonic crystal layer is provided on the upper surface side of the first semiconductor layer. In plan view, the semiconductor stacked body includes a surface-emitting region including the photonic crystal layer and a current injection region. The upper electrode is provided on the current injection region.

Growing community of inventors

Fujisawa, Japan

Tsutomu Kakuno