The Furukawa Electric Co., Ltd.

Yokohama National University

Kazuaki Kiyota

Toshihito Suzuki

Tatsuya Kimoto

Yasumasa Kawakita

Yusuke Saito

Masaki Funabashi

Yasutaka Higa

Tatsuro Kurobe

Masahiro Yoshida

Hideaki Hasegawa

Kazutaka Nara

Junji Yoshida

Toshihiko Baba

Noriyuki Yokouchi

Maiko Ariga

Akira Itoh

Yusuke Inaba

Go Kobayashi

Takeshi Akutsu

A semiconductor optical amplifier array device includes: a substrate; and a plurality of semiconductor optical amplifiers formed on the substrate, each of the semiconductor optical amplifiers including an active region, and two input-output ports optically connected to the active region and disposed on same facet of the semiconductor optical amplifier array device. The plurality of semiconductor optical amplifiers include a first semiconductor optical amplifier in which length of the active region is equal to a first length, and a second semiconductor optical amplifier in which length of the active region is equal to a second length that is different from the first length.

Semiconductor optical amplifier array device

An optical functional device includes: first and second optical couplers each including a multi-mode interferometer waveguide portion having a first end portion and a second end portion, two units of first input/output ports and two units of second input/output ports; and first and second arc-shaped waveguides each optically connecting one of the first and second input/output ports of the first and second optical coupler and one of the first and second input/output ports of the second optical coupler, respectively. Further, the first optical coupler, the second optical coupler, the first arc-shaped waveguide, and the second arc-shaped waveguide constitute a ring resonator, and each of the multi-mode waveguide portions of the first optical coupler and the second optical coupler have a narrow portion, an average width of the narrow portion in a longitudinal direction being narrower than widths at the first end portion and the second end portion.

Optical functional device and laser device

A waveguide based wavelength-tunable laser formed on a semiconductor substrate includes a first reflector from which laser light is output, a second reflector configuring a laser resonator together with the first reflector, a gain portion that is provided between the first reflector and the second reflector, at least two wavelength filters that can adjust wavelength characteristics and adjust a wavelength of the laser light, and a phase adjuster that adjusts an optical path length in the laser resonator, and a waveguide is formed to fold back an optical path by an angle of substantially 180 degrees between the first reflector and the second reflector.

Wavelength-tunable laser and optical module

A semiconductor laser array includes: a plurality of semiconductor lasers configured to oscillate in a single mode at oscillation wavelengths different from one another, each semiconductor laser including an active layer including a multi-quantum well structure including a plurality of will layers and a plurality of barrier layers laminated alternately, and an n-side separate confinement heterostructure layer and p-side separate confinement heterostructure layer configured to sandwich the active layer therebetween in a thickness direction, band gap energies of the n-side separate confinement heterostructure layer and the p-side separate confinement heterostructure layer being greater than band gap energies of the barrier layers of the active layer. The active layer is doped with an n-type impurity.

Semiconductor laser array, semiconductor laser element, semiconductor laser module, and wavelength-variable laser assembly

An optical integrated element includes: a substrate; a first waveguide region in which a lower cladding layer, a first core layer, and an upper cladding layer are sequentially laminated in this order on the substrate; and an active region in which the lower cladding layer, a second core layer, a quantum well layer that amplifies light when a current is injected, and the upper cladding layer are sequentially laminated on the substrate. Further, the second core layer and the quantum well layer are close to each other within a range of a mode field of light guided in the second core layer, and the first core layer is butt-jointed to the second core layer and the quantum well layer.

Optical integrated element and optical module

A laser device includes a wavelength-tunable laser including plural wavelength selectors in an optical resonator; a semiconductor optical amplifier that amplifies the laser light input thereto; a light intensity variation detector that detects variation in intensity of the laser light output from the wavelength-tunable laser before the laser light is input to the semiconductor optical amplifier; a wavelength dithering generation unit that generates a resonator mode wavelength dithering to modulate a resonator mode of the resonator; a wavelength dithering feedback controller that performs, on the resonator mode wavelength dithering, feedback control based on the variation in intensity detected by the light intensity variation detector; a light intensity detector that detects an intensity of the laser light output from the semiconductor optical amplifier; and a semiconductor optical amplifier feedback controller that performs feedback control on the semiconductor optical amplifier based on the intensity detected by the light intensity detector.

Wavelength-tunable laser device

A semiconductor laser device is a vernier-type wavelength-tunable semiconductor laser device including an optical resonator, constituted by first and second reflective elements having reflection comb spectra in which reflection peaks are arranged on a wavelength axis in a substantially periodic manner and having mutually different periods. At least one of the first and second reflective elements has a sampled grating structure having a reflection comb spectrum in which reflection phases at the respective reflection peaks are aligned and the intensity of a reflection peak outside a set laser emission wavelength bandwidth is lower than the intensity of a reflection peak within the laser emission wavelength bandwidth.

Semiconductor laser device, diffraction grating structure, and diffraction grating

A laser module that can suppress influence due to a reflected light between chips is provided. A laser moduleaccording to one embodiment of the present invention includes: a laser elementprovided on a first substrate and having a laser oscillation unit that generates a laser light and a first optical waveguide that guides the laser light; and an optical amplifierprovided on a second substrate and having a second waveguide that guides the laser light. The first optical waveguide is nonparallel relative to an end face of the first substrate and connected thereto, the second optical waveguide is nonparallel relative to an end face of the second substrate and connected thereto, and the first substrate and the second substrate are arranged such that the laser light output from the first optical waveguide is optically coupled to the second optical waveguide.

Laser module

A disclosed semiconductor laser device includes a distributed feedback portion serving as a light-emittable active region the distributed feedback portion having a diffraction grating; and a distributed reflective portion serving as a passive reflective mirror, the distributed reflective portion having a diffraction grating, wherein the distributed feedback portion includes a first region adjacent to the distributed reflective portion and having a diffraction grating having a predetermined standard period, a phase shift region adjacent to the first region, the phase shift region being longer by twice or more than the standard period, and a second region adjacent to an opposite side to the first region of the phase shift region and having a diffraction grating with the standard period, and the phase shift region optically changes a phase of laser beam between the first region and the second region.

Semiconductor laser device

A semiconductor laser apparatus includes a semiconductor optical integrated device including a semiconductor laser array including a plurality of semiconductor laser elements, a semiconductor arrayed waveguide grating, made of a semiconductor, including an inputting slab waveguide connected to the plurality of the semiconductor laser elements, an array waveguide connected to the inputting slab waveguide and including a plurality of waveguides having different lengths from each other and arranged in a parallel manner, and an outputting slab waveguide connected to the array waveguide; a substrate on which the semiconductor laser array and the semiconductor arrayed waveguide grating are monolithically integrated; and an output facet outputting a laser light emitted from the semiconductor laser elements and including an output end of the outputting slab waveguide.

Semiconductor laser apparatus

A semiconductor optical integrated device includes: a substrate; at least a lower cladding layer, a waveguide core layer, and an upper cladding layer sequentially layered on the substrate, a buried hetero structure waveguide portion having a waveguide structure in which a semiconductor cladding material is embedded near each of both sides of the waveguide core layer; and a ridge waveguide portion having a waveguide structure in which a semiconductor layer including at least the upper cladding layer protrudes in a mesa shape. Further, a thickness of the upper cladding layer in the buried hetero structure waveguide portion is greater than a thickness of the upper cladding layer in the ridge waveguide portion.

Semiconductor optical integrated device having buried hetero structure waveguide and deep ridge waveguide

An optical semiconductor apparatus includes: semiconductor laser devices having different emission wavelengths and grouped into at least a first group and a second group; and an arrayed waveguide grating connected to the semiconductor laser devices of the first and second groups and configured to combine laser light beams radiating from the semiconductor laser devices into a same point. The arrayed waveguide grating is configured to combine laser light beams from the semiconductor laser devices belonging to the first group into the same point by diffraction in a first diffraction order in the arrayed waveguide grating, and combine laser light beams from the semiconductor laser devices belonging to the second group into the same point by diffraction in a second diffraction order different from the first diffraction order, in the arrayed waveguide grating.

Optical semiconductor apparatus

A semiconductor optical integrated device includes: a substrate; at least a lower cladding layer, a waveguide core layer, and an upper cladding layer sequentially layered on the substrate, a buried hetero structure waveguide portions each having a waveguide structure in which a semiconductor cladding material is embedded near each of both sides of the waveguide core layer; and a ridge waveguide portion having a waveguide structure in which a semiconductor layer including at least the upper cladding layer protrudes in a mesa shape. Further, a thickness of the upper cladding layer in each of the buried hetero structure waveguide portions is greater than a thickness of the upper cladding layer in the ridge waveguide portion.

Semiconductor optical integrated device including a reduced thickness upper cladding layer in a ridge waveguide portion, and method of manufacturing the same

A semiconductor optical element includes an optical waveguide formed on a semiconductor substrate, which includes: a single mode guide portion which guides input light in a single mode; a curved portion disposed at a downstream side of the single mode guide portion in a waveguide direction of the light and guiding the light in a single mode; and a flared portion disposed at a downstream side of the curved portion in the waveguide direction and of which waveguide width is widened toward the waveguide direction, so that the flared portion can guide the light in a single mode at an light-input side and the flared portion can guide the light in a multi-mode at a light-output side. The input light is optically-amplified by each of the active layers in the single mode guide portion, the curved portion and the flared portion by an optically-amplifying effect of the active layers.

Semiconductor optical element, integrated semiconductor optical element, and semiconductor optical element module

An optical amplifier device comprising an input/output section that inputs incident light and outputs emission light; a polarized light splitting section that causes a polarized light component of the incident light input from the input/output section to branch, and outputs first polarization mode light having a first polarization and second polarization mode light having a second polarization different from the first polarization; a polarization converting section that receives the first polarization mode light, converts the first polarization to the second polarization, and outputs first polarization converted light; and an optical amplifying section that amplifies the first polarization converted light input to one end of a waveguide, outputs the resulting amplified first polarization converted light from another end of the waveguide, amplifies the second polarization mode light input to the other end of the waveguide, and outputs the resulting amplified second polarization mode light from the one end of the waveguide.

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Tokyo, Japan

Kazuaki Kiyota