Telecommunications and Energy Laboratories

United States

Telecommunications and Energy Laboratories

United States
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Kiyota K.,Telecommunications and Energy Laboratories | Okuyama S.,Telecommunications and Energy Laboratories
Furukawa Review | Year: 2017

A narrow spectral linewidth is required for both the signal light source and the local oscillator light source in a digital coherent communication. The use of a DR laser with a combination of a conventional Distributed Feedback (DFB) laser and a Distributed Bragg Reflector (DBR) mirror shows promise for improving the characteristic of the spectral linewidth. We devised a configuration employing an etched core type DBR for a DR laser, where an active layer as a waveguide core is periodically etched. We have achieved a line-width of less than 150 kHz by applying this etched core type DR laser to the laser part of a wide wavelength tunable light source.


Maeda K.,Telecommunications and Energy Laboratories | Takasaka S.,Telecommunications and Energy Laboratories | Sugizaki R.,Telecommunications and Energy Laboratories | Tsuchida Y.,A-D Technologies | And 2 more authors.
Furukawa Review | Year: 2017

We have developed a multicore erbium doped fiber (MC-EDF) with an increased absorption coefficient for the batch pumping. We fabricated a cladding-pumped type amplifier using the developed fiber and realized a gain of 18.0 dB, a noise figure (NF) of 6.1 dB and a core to core crosstalk of -44.0 dB in the C-band.


Kagoura T.,Telecommunications and Energy Laboratories | Kimura A.,Underground Power | Tateno Y.,VISCAS Corporation
Furukawa Review | Year: 2016

In the Fukushima Floating Offshore Wind Farm Demonstration Project (Fukushima FORWARD Project), which is a commissioned business from Ministry of Economy, Trade and Industry, Furukawa Electric (FEC) is in charge of a power cable transmission system. FEC have designed a riser cable which has been connected to the world's largest 7 MW class floating offshore wind turbine generator. Pursuant to the completion of the project, we are issuing this report.


Sasaki H.,A-D Technologies | Minato R.,Telecommunications and Energy Laboratories
Furukawa Review | Year: 2015

The observation of the Gallium arsenide (GaAs) model specimen and the analysis of the semiconductor laser diode were carried out by using the electron holography, which is one of the methods of the transmission electron microscope, and Lorentz microscopy. In the observation using the electron holography, not only pn junction but also interfaces which are in different dopant concentration regions of the 1×1019 and 1×1018 cm-3 regions and the 1×1018 and 1×1017 cm-3 regions could be observed. Then, the analysis example for the semiconductor laser diode was introduced and described that these methods have been used practically.


Iwai N.,A-D Technologies | Wakaba M.,A-D Technologies | Kiyota K.,Telecommunications and Energy Laboratories | Kurobe T.,A-D Technologies | And 6 more authors.
Furukawa Review | Year: 2015

Recently, a power consumption reduction is required for optical components used in optical communications. For a light signal source module that uses temperature control components for a precision control of wavelength, semi-cooled performance is useful for the purpose of low power consumption, because the semi-cooled performance raises the operation temperature range of the laser chips higher than ever before. In this case, since the laser chip is required to show superior performances at high temperature, using AlGaInAs-based materials, which are suitable for the performances at high temperature, in an active layer of the signal light source is a promising technology for the reduction of power consumption. On the other hand, a photonic integrated circuit (PIC) is a key technology to achieve both a size reduction and a low power consumption in the development of the next-generation of the optical communication systems. Here with the aim of realizing a high-performance photonic integrated circuit, we are reporting our development of a 1550 nm AlGaInAs buried-heterostructure laser and also the fabrication of a 1550 nm wavelength tunable laser, as the first for an AlGaInAs/InP-based laser, which is integrated with a 12 channel-DFB (Distributed feedback) laser array and a semiconductor optical amplifier (SOA).


Nakao K.,Telecommunications and Energy Laboratories | Kasahara H.,Telecommunications and Energy Laboratories | Hatakeyama H.,Telecommunications and Energy Laboratories | Matsuoka T.,Telecommunications and Energy Laboratories | Mukoyama S.,Telecommunications and Energy Laboratories
Furukawa Review | Year: 2016

Because of a large demand of a low carbon society, the dependence rate on renewable power sources, such as solar power generators and wind power generators, is increasing. A flywheel energy storage system, which can charge and discharge the electrical power rapidly has been developed, in combination with the development of the unstable renewable power source, in order to stabilize a power system and a regenerative power recovery system of a rail system in The New Energy and Industrial Technology Development (NEDO) project. The flywheel energy system charges electrical power from the kinetic energy of a rotating flywheel, and discharges the power transforming the kinetic energy back into electrical power. Furukawa Electric developed a superconducting magnetic bearing (SMB) combining a Rare Earth Ba2Cu3Oy (REBCO) high temperature superconducting coil with a high temperature superconducting bulk, and succeeded to achieve a non-contact levitation and a non-contact rotation of a rotor of 4 tons. In this paper, a design process, a trial manufacturing and a performance test of the SMB are reported.


Yamamoto A.,A-D Technologies | Okaniwa T.,A-D Technologies | Yafuso Y.,A-D Technologies | Nishita M.,Telecommunications and Energy Laboratories
Furukawa Review | Year: 2015

A Micro Integrable Tunable Laser Assembly (Micro ITLA) downsized by one-third (37.5×20.0 mm2) of the standard ITLA is developed. The Micro ITLA has the feature of improving a higher output power and a narrower spectrum linewidth while maintaining the function of the specification of the standard ITLA1), and developing a compacted package module and a control circuit technology implemented with respect to the standard specification of the Micro ITLA2). Furthermore, the spectrum linewidth of less than 300 kHz and the gridless wavelength output capacity (a minimum setting resolution: 0.1 GHz) were satisfied with a system requirement of more than 400 Gb/s.

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