Zobrazeno 1 - 10
of 10
pro vyhledávání: '"Chikara Watatani"'
Autor:
Keiichi Edamatsu, Kenzo Maehashi, Tadashi Itoh, Hisao Nakashima, Takeshi Ota, Kenichi Oto, Kazuo Murase, Chikara Watatani, Yasuhiro Murase
Publikováno v:
Journal of Electronic Materials. 30:448-452
We have investigated carrier relaxation dynamics in single CdSe/ZnSe quantum dot (QD) by time-resolved micro-photoluminescence (PL). The discrete sharp lines, originated from individual QD states, exhibit various rise and decay time constants. The de
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::1c8993c7f8d1d7357a5fd8b5df51bfdc
https://doi.org/10.1007/s11664-001-0081-4
https://doi.org/10.1007/s11664-001-0081-4
Autor:
Kazuhisa Takagi, Chikara Watatani, Tohru Takiguchi, S. Shirai, Toshitaka Aoyagi, Nobuyuki Tomita, T. Nishimura, T. Ota, Y. Tatsuoka
Publikováno v:
IEEE Photonics Technology Letters. 16:2415-2417
A 1.3-/spl mu/m AlGaInAs multiquantum well ridge waveguide distributed feedback laser diode was developed. By forming n-InGaAsP grating in the n-InP cladding layer close to the active region, accumulation of the holes in the grating layer was reduced
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::51bed6e5264572675f934026a8f1f2dd
https://doi.org/10.1109/lpt.2004.834926
https://doi.org/10.1109/lpt.2004.834926
Autor:
Eitaro Ishimura, Takeshi Saito, Akihiro Shima, Toshitaka Aoyagi, Chikara Watatani, Yoshimichi Morita, Keisuke Matsumoto, Tohru Takiguchi, Mitsunobu Gotoda, Kazuhisa Takagi, Susumu Hatakenaka, Koichi Akiyama
Publikováno v:
Optical Fiber Communication Conference/National Fiber Optic Engineers Conference 2011.
A 40G RZ-DQPSK transmitter monolithically integrated with a tunable DFB laser array and Mach-Zehnder modulators was developed for the first time. The optical waveform of 40Gb/s DQPSK was successfully demonstrated.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::7036c9d81f3e1ec410b38c7a877697fb
https://doi.org/10.1364/ofc.2011.omu3
https://doi.org/10.1364/ofc.2011.omu3
Autor:
T. Takiguchi, Hitoshi Sakuma, Suzuki Daisuke, Go Sakaino, Takashi Nagira, Takahide Ishikawa, Toshitaka Aoyagi, Chikara Watatani
Publikováno v:
22nd IEEE International Semiconductor Laser Conference.
1.3µm-band BH AlGaInAs DFB lasers with p-InP substrate are fabricated for 100GbE (25Gbps × 4 wavelengths). Very high mask margin of over 30% is achieved at 50oC under 25.8Gbps modulation with low operation current.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::3bfedfa5c038029db70048e3baaacbad
https://doi.org/10.1109/islc.2010.5642644
https://doi.org/10.1109/islc.2010.5642644
Autor:
Toshitaka Aoyagi, Takahide Ishikawa, Hitoshi Sakuma, Chikara Watatani, Ryota Takemura, Takashi Nagira, Suzuki Daisuke, Masaharu Nakaji
Publikováno v:
36th European Conference and Exhibition on Optical Communication.
Four-channel surface-illuminated photodiodes monolithically integrated in one array chip are fabricated for 100Gbps Ethernet. The photodiode with an optimized distributed Bragg reflector has a 3dB bandwidth of 25GHz and the highest responsivity of 0.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::83711119c3fca01ca08b4f808c494ef2
https://doi.org/10.1109/ecoc.2010.5621249
https://doi.org/10.1109/ecoc.2010.5621249
Autor:
Masayoshi Takemi, Kazuhisa Takagi, Chikara Watatani, Etsuji Omura, S. Shirai, Toshitaka Aoyagi, T. Ota
Publikováno v:
16th IPRM. 2004 International Conference on Indium Phosphide and Related Materials, 2004..
1.3 /spl mu/m AlGaInAs-MQW ridge waveguide DFB-LDs with a buried grating close to active layer in n-cladding layer was developed. The light output power over 5 mW and clear eye opening with no mask hits for OC-192 under 10 Gbps direct modulation have
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::188789fc833a0c17e6c66d8e2394babd
https://doi.org/10.1109/iciprm.2004.1442830
https://doi.org/10.1109/iciprm.2004.1442830
Publikováno v:
16th IPRM. 2004 International Conference on Indium Phosphide and Related Materials, 2004..
We have investigated a real-time reflectance spectroscopy during AlGaInP growth by metalorganic vapor phase epitaxy. The analysis of Fabry-Perot oscillation gives the optical parameters of epitaxial layer such as refractive index (n) and extinction c
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::d6cbe9c48891778ed53359558220ac5f
https://doi.org/10.1109/iciprm.2004.1442607
https://doi.org/10.1109/iciprm.2004.1442607
Autor:
Satoshi Shirai, Tohru Takiguchi, T. Nishimura, Toshitaka Aoyagi, Kazuhisa Takagi, Chikara Watatani, Yutaka Mihashi
Publikováno v:
SPIE Proceedings.
We have proved that short cavity length and large coupling coefficient structure can increase the relaxation oscillation frequency of directly modulated 1.3mm DFB-LDs for 10Gb/s operation. The grating with large coupling coefficient can be made of hi
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::a406c48b43106895ca3241442612913e
https://doi.org/10.1117/12.570996
https://doi.org/10.1117/12.570996
Autor:
Tomoko Kadowaki, Nobuyuki Tomita, Tohru Takiguchi, Chikara Watatani, Masayoshi Takemi, Y. Hanamaki, Etsuji Omura, Toshio Tanaka, Y. Mihashi
Publikováno v:
Optical Fiber Communication Conference and Exhibit.
1.3 /spl mu/m uncooled AlGaInAs DFB-LDs with /spl lambda//4shifted grating have been successfully demonstrated. Relaxation oscillation frequency as high as 11.5 GHz has been obtained. Clear opening in the eye diagram under 10 Gbps direct modulation a
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::a86d408e4e36680b8c3121b1725e82b4
https://doi.org/10.1109/ofc.2002.1036455
https://doi.org/10.1109/ofc.2002.1036455
Autor:
K. Takagi, S. Shirai, Y. Tatsuoka, C. Watatani, T. Ota, T. Takiguchi, T. Aoyagi, T. Nishimura, N. Tomita
Publikováno v:
IEEE Photonics Technology Letters; Nov2004, Vol. 16 Issue 11, p2415-2417, 3p