Search Results - "Takemasa, Keizo"

Development of Quantum Dot Lasers for Data-Com and Silicon Photonics Applications by Nishi, Kenichi, Takemasa, Keizo, Sugawara, Mitsuru, Arakawa, Yasuhiko

“…The device characteristics of semiconductor lasers have been improved with progress in active layer structures. Carrier confinement dimension plays an…”
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Epitaxially regrown quantum dot photonic crystal surface emitting lasers by Kyaw, Aye S. M., King, Ben C., McKenzie, Adam F., Bian, Zijun, Kim, Daehyun, Gerrard, Neil D., Nishi, Kenichi, Takemasa, Keizo, Sugawara, Mitsuru, Childs, David T. D., Hill, Calum H., Taylor, Richard J. E., Hogg, Richard A.

“…Quantum dot-based epitaxially regrown photonic crystal surface emitting lasers are demonstrated at room temperature. The GaAs-based devices, which are…”
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Coherent power scaling in photonic crystal surface emitting laser arrays by King, Ben C., Rae, Katherine J., McKenzie, Adam F., Boldin, Aleksandr, Kim, Daehyun, Gerrard, Neil D., Li, Guangrui, Nishi, Kenichi, Takemasa, Keizo, Sugawara, Mitsuru, Taylor, Richard J. E., Childs, David T. D., Hogg, Richard A.

“…A key benefit of photonic crystal surface emitting lasers (PCSELs) is the ability to increase output power through scaling the emission area while maintaining…”
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Impact of low-temperature cover layer growth of InAs/GaAs quantum dots on their optical properties by Okumura, Shigekazu, Fujisawa, Kazuki, Naruke, Tamami, Nishi, Kenichi, Onishi, Yutaka, Takemasa, Keizo, Sugawara, Mitsuru, Sugiyama, Masakazu

“…The effect of low-temperature InGaAs/GaAs cover layer growth of InAs quantum dots on their optical and structural properties was investigated…”
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Direct modulation of 1.3 μm quantum dot lasers on silicon at 60 °C by Jhang, Yuan-Hsuan, Mochida, Reio, Tanabe, Katsuaki, Takemasa, Keizo, Sugawara, Mitsuru, Iwamoto, Satoshi, Arakawa, Yasuhiko

“…We demonstrate direct modulation of an InAs/GaAs quantum dot (QD) laser on Si. A Fabry-Pérot QD laser was integrated on Si by an ultraviolet-activated direct…”
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Impact of dislocations in InAs quantum dot with InGaAs strain-reducing layer structures on their optical properties by Okumura, Shigekazu, Fujisawa, Kazuki, Yamaguchi, Masaomi, Naruke, Tamami, Nishi, Kenichi, Takemasa, Keizo, Sugawara, Mitsuru, Sugiyama, Masakazu

“…InAs quantum dots with InGaAs strain-reducing layer on GaAs(001) grown at three different temperatures were investigated from the aspect of both structural and…”
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Systematic Study of External Optical Feedback Tolerance in 1300 nm Quantum Dot Lasers by Sobhani, Soroush A., Hogg, Richard A., Takemasa, Keizo, Nishi, Kenichi, Sugawara, Mitsuru, Childs, David T. D.

“…Resilience of 1300nm In(Ga)As/GaAs quantum dot lasers to external optical feedback is systematically investigated from − 10°C to 85 °C. The high-resolution…”
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Proposal for Common Active 1.3- \mu m Quantum Dot Electroabsorption Modulated DFB Laser by Sobhani, Soroush A., Stevens, Ben J., Babazadeh, Nasser, Takemasa, Keizo, Nishi, Kenichi, Sugawara, Mitsuru, Hogg, Richard A., Childs, David T. D.

“…Opportunities for the monolithic integration of a novel common quantum dot (QD)-active electroabsorption modulated laser are explored. An electric-field and…”
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Proposal for Common Active 1.3-[Formula Omitted]m Quantum Dot Electroabsorption Modulated DFB Laser by Sobhani, Soroush A, Stevens, Ben J, Babazadeh, Nasser, Takemasa, Keizo, Nishi, Kenichi, Sugawara, Mitsuru, Hogg, Richard A, Childs, David T D

“…Opportunities for the monolithic integration of a novel common quantum dot (QD)-active electroabsorption modulated laser are explored. An electric-field and…”
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InAs/GaAs quantum dot lasers with GaP strain-compensation layers grown by molecular beam epitaxy by Kageyama, Takeo, Watanabe, Katsuyuki, Vo, Quoc Huy, Takemasa, Keizo, Sugawara, Mitsuru, Iwamoto, Satoshi, Arakawa, Yasuhiko

“…The strain‐compensation (SC) technique to reduce the accumulation of strain is a promising approach to increase the design flexibility as well as the…”
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InAs/GaAs quantum dot lasers with GaP strain-compensation layers grown by molecular beam epitaxy: InAs/GaAs QD lasers with GaP strain-compensation layers by Kageyama, Takeo, Watanabe, Katsuyuki, Vo, Quoc Huy, Takemasa, Keizo, Sugawara, Mitsuru, Iwamoto, Satoshi, Arakawa, Yasuhiko

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Thermal Properties of 1.3 µm AlGaInAs Multi Quantum Well Ridge Waveguide Lasers by Kubota, Munechika, Hamano, Kayo, Takemasa, Keizo, Kobayashi, Masao, Wada, Hiroshi, Munakata, Tsutomu

“…We have fabricated 1.3 µm AlGaInAs/InP multi-quantum-well (MQW) ridge waveguide lasers with both junction-up and junction-down mounting, and compared the…”
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Growth of high-density 1.06-μm InGaAs/GaAs quantum dots for high gain lasers by molecular beamepitaxy by Watanabe, Katsuyuki, Akiyama, Tomoyuki, Yokoyama, Yoshitaka, Takemasa, Keizo, Nishi, Kenichi, Tanaka, Yu, Sugawara, Mitsuru, Arakawa, Yasuhiko

“…We have progressed the growth procedure for high-density highly-uniform In(Ga)As/GaAs quantum dots (QDs) by using molecular beam epitaxy and have demonstrated…”
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1064-nm DFB laser diode modules applicable to seeder for pulse-on-demand fiber laser systems by Yokoyama, Yoshitaka, Takada, Kan, Kageyama, Takeo, Tanaka, Shin, Kondo, Hayato, Kanbe, Satoshi, Maeda, Yasunari, Mochida, Reio, Nishi, Kenichi, Yamamoto, Tsuyoshi, Takemasa, Keizo, Sugawara, Mitsuru, Arakawa, Yasuhiko

“…Semiconductor DFB (Distributed feedback) laser diodes with an operating wavelength of 1064nm, which is suitable for pulse-on-demand fiber laser, have been…”
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Growth of high-density 1.06-μm InGaAs/GaAs quantum dots for high gain lasers by molecular beam epitaxy by WATANABE, Katsuyuki, AKIYAMA, Tomoyuki, YOKOYAMA, Yoshitaka, TAKEMASA, Keizo, NISHI, Kenichi, TANAKA, Yu, SUGAWARA, Mitsuru, ARAKAWA, Yasuhiko

“…We have progressed the growth procedure for high-density highly-uniform In(Ga)As/GaAs quantum dots (QDs) by using molecular beam epitaxy and have demonstrated…”
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Photoreflectance Study of Interface Roughness in Ge/SiGe Strained-Layer Heterostructures by Hiroyuki Yaguchi, Hiroyuki Yaguchi, Kaori Tai, Kaori Tai, Keizo Takemasa, Keizo Takemasa, Kentaro Onabe, Kentaro Onabe, Yasuhiro Shiraki, Yasuhiro Shiraki, Ryoichi Ito, Ryoichi Ito

“…Ge/SiGe strained-layer heterostructures have been investigated using photoreflectance (PR) spectroscopy. On the basis of the comparison between the…”
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Confirmation of AlGaAs crystal domain inversion using asymmetric wet etching and optical second-harmonic generation methods by XU, C.-Q, TAKEMASA, K, NAKAMURA, K, WADA, H, TAKAMORI, T, OKAYAMA, H, KAMIJOH, T

“…The occurrence of crystal domain inversion on a (001) GaAs substrate was confirmed by a direct observation method based on asymmetric wet etching of AlGaAs and…”
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Epitaxially Regrown Quantum Dot Photonic Crystal Surface Emitting Laser by Kyaw, Aye S. M., King, Ben C., McKenzie, Adam F., Gerrard, Neil D., Bian, Zijun, Kim, Daehyun, Liu, Jingzhao, Zhao, Xingyu, Nishi, Kenichi, Takemasa, Keizo, Sugawara, Mitsuru, Childs, David T. D., Hill, Calum H., Taylor, Richard J. E., Hogg, Richard A.

“…Quantum dot based epitaxially regrown photonic crystal surface-emitting lasers (PCSELs) are demonstrated at room temperature. The GaAs based devices exhibit…”
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High Temperature Operation of AlGaInAs Ridge Waveguide Lasers with a p-AlInAs Electron Stopper Layer by Takemasa, Keizo, Munakata, Tsutomu, Kobayashi, Masao, Wada, Hiroshi, Kamijoh, Takeshi

“…1.3 µm AlGaInAs/InP ridge waveguide lasers with a p-AlInAs electron stopper layer (ESL) were fabricated and the effect of the ESL was investigated. By…”
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AlGaAs Semiconductor Quasiphase-Matched Wavelength Converters by Xu, Chang-qing, Takemasa, Keizo, Nakamura, Koji, Okayama, Hideaki, Kamihoh, Takeshi

“…Wavelength conversion based on sum frequency generation (SFG) using a semiconductor quasiphase-matched (QPM) waveguide with a periodically crystal domain…”
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