The Furukawa Electric Co., Ltd.

University of Illinois

Advanced Telecommunications Research Institute International

Toshihiko Baba

Noriyuki Yokouchi

Norihiro Iwai

Tatsuyuki Shinagawa

Junji Yoshida

Hideaki Hasegawa

Masaki Funabashi

Kazutaka Nara

Akihiko Kasukawa

Takeshi Akutsu

Tatsuya Kimoto

Takeharu Yamaguchi

Tomofumi Kise

Natsumi Ueda

Junichi Hasegawa

Yasumasa Kawakita

Kazuaki Kiyota

Kent D Choquette

Satoshi Irino

Kengo Watanabe

Toshikazu Mukaihara

Kazuaki Nishikata

Taketsugu Sawamura

Nobumitsu Yamanaka

Tatsuro Kurobe

Kengo Muranushi

Masato Tachibana

Sayoko Ibe

Takahisa Harayama

Takehiro Fukushima

Shuichi Tamura

Keizou Inagaki

Morito Matsuoka

An optical power transmission apparatus includes: a light emitting unit including a first optical gain generating means and a first light reflecting means; an optical fiber; a second light reflecting means; and a light receiving means. Further, the second light reflecting means is arranged nearer to the light receiving means than the optical fiber is, a first laser resonator is formed, between the first light reflecting means and the second light reflecting means, by optical connection between the first optical gain generating means and the optical fiber, and first laser light generated by the first laser resonator is configured to be incident on the light receiving means.

Optical power transmission apparatus

A semiconductor optical device includes an active layer, the active layer including a plurality of quantum well layers having gain peak wavelengths different from one another in a layering direction thereof, and a plurality of barrier layers, wherein the quantum well layers and the barrier layers are alternately layered over each other, and an n-type dopant has been added in the plurality of quantum well layers having gain peak wavelengths different from one another and in the plurality of barrier layers.

Semiconductor optical device

A method of designing a semiconductor laser device includes: controlling a distance between the output-side reflection unit and the second reflection unit and an effective optical feedback &#x3ba; to the semiconductor laser element, the effective optical feedback &#x3ba; defined by a below-presented formula (1) including a circulating time &#x3c4; of the light in the semiconductor laser element, a reflectivity Rof the output-side reflection unit, and a reflectivity Rof the second reflection unit; selecting a semiconductor laser device in which an LFF period is equal to or smaller than 20 ns as a semiconductor laser device in which high speed switching occurs between an FBG mode and an FP mode; and using the selected semiconductor laser device as an semiconductor laser device oscillating in a coherent collapse mode.&#x3ba;=(1/&#x3c4;)&#xd7;(1&#x2212;)&#xd7;()&#x2003;&#x2003;(1)

Method of designing semiconductor laser device, method of designing raman amplifier, methods of manufacturing semiconductor laser device, semiconductor laser device, raman amplifier, and optical communication system

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.

Optical amplifier device

The invention of the present application provides an SOA-PLC hybrid integrated polarization diversity circuit including a PLC-PBS chip and an SOA-COS whose respective waveguides are coupled to each other. The PLC-PBS chip includes: first and second optical waveguides; a Mach-Zehnder interferometer circuit; and a half-wave plate placed in the first optical waveguide which TM mode light is split into. The SOA-COS includes: a third optical waveguide connected to the first optical waveguide; a fourth optical waveguide connected to the second optical waveguide; and an SOA formed in at least one of the third and fourth optical waveguides. One end of the third optical waveguide and one end of the fourth optical waveguide are connected to a U-turn optical waveguide, the one ends being not connected to the first optical waveguide and the second optical waveguide, respectively.

SOA-PLC hybrid integrated polarization diversity circuit and method for manufacturing the same

It is desirable to provide a semiconductor optical amplifier from which it becomes able to obtain a higher output power. A semiconductor optical amplifier in comprises an active wave guiding layer which comprises a passive core region that is formed of a semiconductor, and active cladding regions that are located at both sides of the passive core region and each of that is comprised of an active layer which is formed of a semiconductor and which has an index of refraction to be lower than that of the passive core region, wherein a light is wave guided with being amplified in the active wave guiding layer. Moreover, it is desirable for the active wave guiding layer to be formed of a compound semiconductor, and to be formed by integrating the passive core region and the active cladding regions to be monolithic on to a substrate that is formed of a compound semiconductor by making use of a process of a butt joint growth.

Semiconductor optical amplifier

A surface emitting laser is provided with an upper reflecting mirror having a photonic crystal structure with a point defect at the center, and emits a laser beam from the side of a lower reflecting mirror. An upper electrode is formed on the point defect at the center, and element resistance is reduced. A material transparent to a wavelength of the laser beam is used for a substrate. The emission efficiency is improved by reducing the element resistance of the photonic crystal surface emitting laser.

Surface emitting semiconductor laser element

A surface-emitting semiconductor laser device includes a semi-insulating substrate, a layer structure with a bottom multilayer reflector, an n-type cladding layer, an active layer structure for emitting laser, a p-type cladding layer and a top multilayer reflector with a dielectric material, consecutively formed on the semi-insulating substrate, the active layer structure, the p-type cladding layer and the top multilayer reflector, configuring a mesa post formed on a portion of the n-type cladding layer, the p-type cladding layer or the p-type multilayer reflector. The surface-emitting semiconductor laser includes a p-side electrode formed on another portion of the p-type cladding layer, and an n-side electrode formed on another portion of the n-type cladding layer. The n-side electrode includes a substantially uniform Au film and AuGeNi film or AuGe film consecutively formed on the n-type cladding layer, and an alloy is formed between said Au film and said AuGeNi film or AuGe film.

Surface-emission semiconductor laser device

An optical-waveguide device mounted on a fixing member having a pair of opposing upright walls and a sub-mount unit including a metallic sub-mount of a rectangular solid shape inserted between the opposing upright walls and a nonmetallic sub-mount of a rectangular solid shape mounted on the metallic sub-mount, and fixed onto a base table. The fixing member and the sub-mount unit as well as the fixing member and the base table are spot-welded together using YAG welding.

Optical module

A laser gyro of the present invention includes laser light excitation means (a semiconductor laser device) that excites first and second laser lights propagating in the opposite directions to each other in a circular ring-shaped path (an optical path), coupling means (optical waveguidesand) for superimposing the first and the second laser lights, and a photodetector for observing an interference signal generated by the superimposed first and second laser lights.

Laser gyro and electronic device using the same

An optical integrated circuitaccording to the present invention includes a planar lightwave circuit, and a semiconductor element, which are fixed at one contact surface. A semiconductor optical amplifier (SOA)is formed on a semiconductor substrate. A semiconductor waveguideand a semiconductor waveguideare formed on an input side and an output side of SOA, respectively. The semiconductor waveguidehas a turnaround portionturned around on the semiconductor substrate. Respective ends of the optical waveguidesandon a PLC platformand respective ends of semiconductor waveguidesandare optically coupled with each other at the contact surface

Optical integrated circuit and optical integrated circuit module

To provide a photonic crystal semiconductor device which enables various kinds of optical devices having a photonic crystal structure which is readily formed using a semiconductor and a semiconductor manufacturing process, and a manufacturing method thereof. The object can be achieved by a photonic crystal structure, including a lower DBR layer, a core layer, an upper DBR layer, and a dielectric multilayer filmwhich are sequentially laminated from an n-InP substrateside, a plurality of holesformed in the direction of a film thickness in the core layerand the upper DBR layer, and a line defect portionwith none of the plurality of holes formed therein and disposed between the plurality of holes, wherein the line defect portionserves as an optical waveguide.

Photonic crystal semiconductor device and production method thereof

A method for fabricating a surface-emission semiconductor laser on a p-type substrate includes the step of interposing an Au film between an AuGeNi film or AuGe film of an n-side electrode and a compound semiconductor layer of an n-type DBR, followed by annealing to form an Au alloy in the n-side electrode. The presence of the Au alloy film improves the adherence between the n-side electrode and the compound semiconductor layer to improve an injection current vs. applied voltage characteristic.

A surface emitting semiconductor laser device including a substrate, a bottom DBR, and a mesa post having a layer structure, the layer structure including a top DBR including a plurality of pairs, each of said pairs including an Al-containing high-reflectivity layer and an Al-containing low-reflectivity layer, an active layer structure sandwiched between the DBRs for emitting laser, and a current confinement layer disposed within or in a vicinity of one of the DBRs, the current confinement layer including a central current injection area and an annular current blocking area encircling the central current injection area, the annular current blocking area being formed by selective oxidation of Al in an AlGaAs layer (0.95&#x2266;x&#x3c;1) having a thickness below 60 nm, the Al-containing low-reflectivity layer including Al at an atomic ratio not more than 0.8 and below 0.9. The progress of the oxidation in the Al-containing compound semiconductor layers can be suppressed during the formation of the current confinement oxide area by restricting the Al content in the specified range, thereby realizing the surface emitting semiconductor laser device having the longer lifetime, or the higher reliability.

Surface emitting semiconductor laser device

The invention is directed to a photonic crystal defect structure for a vertical cavity surface emitting laser (VCSEL). In accordance with the invention, a set of holes is formed in a pattern with one or more missing holes forming a defect in the pattern of the photonic crystal, according to a proscribed depth, hole diameter, and pattern pitch which will insure operation in a single transverse mode.

Growing community of inventors

Tokyo, Japan

Noriyuki Yokouchi