28-Gb/s directly modulated InGaAlAs ACPM DFB lasers with high mask margin of 22% at 55°C. - Kouji Nakahara; Yuki Wakayama; K. Hiruma; Takeshi Kitatani; Kazunori Shinoda; T. Fukamachi; Yasushi Sakuma; Shigehisa Tanaka (OFC/NFOEC, 2013)

Uncooled (0 to 85°C) and full C-band operation of a 10.7 Gbit/s InP Mach-Zehnder modulator monolithically integrated with SOA. - Akira Nakanishi; Noriko Sasada; Yasushi Sakuma; Ryu Washino; K. Okamoto; Kazuhiko Naoe; Hiroaki Hayashi; Hideo Arimoto; Shigehisa Tanak (OFC/NFOEC, 2013)

Uncooled clear-eye-opening operation (25 to 95°C) of 25.8/28-Gbps 1.3-µm InGaAlAs-MQW directly modulated DFB lasers. - T. Fukamachi; Atsushi Nakamura; Yasushi Sakuma; Shigenori Hayakawa; Ryu Washino; M. Mukaikubo; K. Okamoto; T. Nakajima; K. Motoda; Kazuhiko Naoe; K. Nakahara; Yuki Wakayama; et al. (OFC, 2014)

56-Gb/s direct modulation in InGaAlAs BH-DFB lasers at 55°C. - Kouji Nakahara; Yuki Wakayama; Takeshi Kitatani; Takafumi Taniguchi; Toshihiko Fukamachi; Yasushi Sakuma; Shigehisa Tanaka (OFC, 2014)

25.8 Gbps error free transmission over 10 km at wavelengths from 1271 to 1331nm by uncooled (25 to 85°C) directly modulated DFB lasers for 100G-CWDM4. - Takayuki Nakajima; T. Fukamachi; Mitsuo Akashi; Atsushi Nakamura; Yasushi Sakuma; Shigenori Hayakawa; Ryu Washino; M. Mukaikubo; K. Okamoto; K. Motoda; Kazuhiko Naoe; K. Nakahara; et al. (OFC, 2015)

Uncooled Operation of 53-Gbaud PAM4 (106-Gb/s) EA/DFB Lasers with Extremely Low Drive Voltage with 0.9 Vpp. - Yoshihiro Nakai; Akira Nakanishi; Yoriyoshi Yamaguchi; Syunya Yamauchi; Atsushi Nakamura; Hideaki Asakura; Hayato Takita; Shigenori Hayakawa; Masatoshi Mitaki; Yasushi Sakuma; Kazuhiro Naoe (ECOC, 2018)

Superior BER Transmission of 106-Gb/s/lane Skewless PAM4 over 10 km by Utilizing 1.3-μm Directly Modulated InGaAlAs-MQW BH Lasers and Incoherent Multiplexing of Two NRZ Signals. - Kouji Nakahara; Riu Hirai; Takeshi Kitatani; Nobuhiko Kikuchi; Takayoshi Fukui; Kaoru Okamoto; Yasushi Sakuma; Kohichi Robert Tamura; Shigehisa Tanaka (OFC, 2018)

Analysis of TDECQ Dependence on Skew and Extinction Ratio with 106-Gb/s PAM-4 Modulation of Directly Modulated Submicron Ridge Localized Buried Heterostructure Lasers. - Kazuki Suga; Kouji Nakahara; Kaoru Okamoto; Shigenori Hayakawa; Masatoshi Arasawa; Tetsuya Nishida; Ryu Washino; Takeshi Kitatani; Masatoshi Mitaki; Hironori Sakamoto; Yasushi Sakuma; Shigehisa Tanaka (OFC, 2020)

Large-Optical-Aperture Top-Illuminated 50-Gbaud PIN-PD with High 3-dB Bandwidth at a Low Bias of 1.5 V. - Takashi Toyonaka; Hiroshi Hamada; Shigehisa Tanaka; Masatoshi Arasawa; Ryu Washino; Yasushi Sakuma; Kazuhiko Naoe (OFC, 2020)

112-Gb/s PAM-4 Uncooled Directly Modulated BH Lasers. - Kouji Nakahara; Kazuki Suga; Kaoru Okamoto; Shigenori Hayakawa; Masatoshi Arasawa; Tetsuya Nishida; Ryu Washino; Takeshi Kitatani; Masatoshi Mitaki; Hironori Sakamoto; Yasushi Sakuma; Shigehisa Tanaka (ECOC, 2021)