"Keisuke Kawahara,Tai Tsuchizawa,Noritsugu Yamamoto,Yuriko Maegami,Koji Yamada,Shinsuke Hara,Toshihiko Baba","High-Efficiency Compact Optical Transmitter With a Total Bit Energy of 0.78 pJ/Bit Including Silicon Slow-Light Modulator and Open-Collector Current-Mode Driver",,"IEEE Journal of Selected Topics in Quantum Electronics",,,,,2026,Mar.
"Haoyu Chen,Moataz Eissa,Kaibin Yao,Tsuyoshi Horikawa,Keisuke Kawahara,Nobuhiko Nishiyama","High-Efficiency Vertical Coupler between Si and Low-index (~1.6) SiON Waveguide with Low Polarization Dependance Loss","The 73rd JSAP Spring Meeting 2026",,,,,,2026,Mar.
"�쌴 Œ[•ã","Œõ“d‹¦’²�ÝŒv‚Ì�Å�V“®Œü",,"Optronics : Œõ‹Z�pƒR�[ƒfƒBƒl�[ƒgƒWƒƒ�[ƒiƒ‹","“Œ‹ž : ƒIƒvƒgƒ�ƒjƒNƒXŽÐ","Vol. 44","No. 11","pp. 130-134",2025,Nov.
"�쌴Œ[•ã,“yàV‘×,ŽR–{�@Œp,‘O�_—L—¢Žq,ŽR“c�_Ž¡,”n�ê�r•F","Œõ“d‹C“™‰»‚É‚æ‚éSiƒtƒHƒgƒjƒbƒNŒ‹�»Œõ•Ï’²Ší‚Ì100 Gbaud“®�ì","‰ž—p•¨—�Šw‰ï �H‹GŠw�p�u‰‰‰ï",,,,,,2025,Sept.
"Toshihiko Baba,Keisuke Kawahara","Slow-light-based modulator and transmitter",,"Active Photonic Platforms (APP) 2025",,,,,2025,Sept.
"Keisuke Kawahara,Tai Tsuchizawa,Noritsugu Yamamoto,Yuriko Maegami,Koji Yamada,Shinsuke Hara,Toshihiko Baba","Optical Transmitter with Silicon Slow-Light Modulator and BiCMOS Current-Mode Driver Achieving 0.78 pJ/bit Total Bit Energy","OECC/PSC 2025",,,,,,2025,July
"Toshihiko Baba,Keisuke Kawahara","High-Efficiency Optical Transmitter Including Si Photonic Crystal Slow-Light Modulator Co-Designed with Driver Amplifier",,"2025 30th OptoElectronics and Communications Conference (OECC) and 2025 International Conference on Photonics in Switching and Computing (PSC)",,,,,2025,June
"”n�ê�r•F,�쌴Œ[•ã","Œõ“d—Z�‡�ÝŒv‚É‚æ‚é�¬Œ^�‚�«”\ƒ}ƒbƒn�EƒcƒFƒ“ƒ_�[Œõ•Ï’²Ší",,"ŒõŠw",,"vol. 54","no. 4","pp. 134-138",2025,Apr.
"Keisuke Kawahara,Toshihiko Baba","Accurate EO co-simulation of Si photonics using a standard electronic circuit simulator",,"Smart Photonic and Optoelectronic Integrated Circuits 2025",,,,,2025,Mar.
"Keisuke Kawahara,Toshihiko Baba","Electro-Optic Co-Simulation in High-Speed Silicon Photonics Transceiver Design Using Standard Electronic Circuit Simulator",,"IEEE Journal of Microwaves",,,,,2025,
"Keisuke Kawahara,Tai Tsuchizawa,Noritsugu Yamamoto,Yuriko Maegami,Koji Yamada,Shinsuke Hara,Toshihiko Baba","High-speed, low-voltage, low-bit-energy silicon photonic crystal slow-light modulator with impedance-engineered distributed electrodes",,"Optica",,,,,2024,Sept.
"Keisuke Kawahara,Toshihiko Baba","DAC- and DSP-Free Optical Transmitter Based on Triple-Parallel Si Mach-Zehnder Modulators",,"2024 IEEE Silicon Photonics Conference (SiPhotonics)",,,,,2024,Apr.
"Keisuke Kawahara,Tai Tsuchizawa,Noritsugu Yamamoto,Yuriko Maegami,Koji Yamada,Toshihiko Baba","59-fJ/bit Si Photonic Crystal Slow-Light Modulator with FinFET-Compatible Driving Voltage",,"Optical Fiber Communication Conference (OFC) 2024",,,,,2024,
"Kawahara, Keisuke,Tsuchizawa, Tai,Yamamoto, Noritsugu,Maegami, Yuriko,Yamada, Koji,Hara, Shinsuke,Baba, Toshihiko,Keisuke Kawahara","1.9-pJ/bit 0.5-mm2 High-Speed Optical Transmitter including Silicon Slow-Light Modulator and Current-Mode BiCMOS Driver",,"ECOC 2024; 50th European Conference on Optical Communication",,,,"pp. 778-781",2024,
"Keisuke Kawahara,Toshihiko Baba","Modeling of Si Rib and Photonic Crystal Mach-Zehnder Modulators for Electro-Optic Co-Simulation up to 64 Gbaud",,"2023 IEEE MTT-S International Conference on Numerical Electromagnetic and Multiphysics Modeling and Optimization (NEMO)",,,,,2023,Aug.
"Keisuke Kawahara,Yohtaro Umeda,Kyoya Takano,Shinsuke Hara","A 0.0058-mm2 Inductor-Less CMOS Active Balun With Gain and Phase Errors Within �|0.1 �} 0.2 dB and �|0.18 �} 1.17�‹ From DC to 8 GHz",,"IEEE Transactions on Circuits and Systems I: Regular Papers",,,,,2023,June
"Keisuke Kawahara,Joe Sawada,Takumi Kamo,Yohtaro Umeda,Kyoya Takano,Shinsuke Hara","Bandwidth Tripler: Broadband Signal Generation With an Image-Rejection Analog Multiplexer for Fiber Optic Transmitters",,"IEEE Transactions on Microwave Theory and Techniques",,,,,2023,Jan.
"Keisuke KAWAHARA,Yohtaro UMEDA,Kyoya TAKANO,Shinsuke HARA","A Compact Fully-Differential Distributed Amplifier With Coupled Inductors in 0.18-ƒÊm CMOS Technology",,"IEICE Transactions on Electronics",,,,,2023,
"�쌴 Œ[•ã,Š™“c Š²–ç,�—‘q —z‰î,‰ª–ì �½,Cong Guangwei,ŽR–{ �@Œp,ŽR“c �_Ž¡,”n�ê �r•F","64 Gbps Si ƒtƒHƒgƒjƒbƒNŒ‹�»Œõ•Ï’²Ší‚Ì•Ï’²Œø—¦‰ü‘P",,"‰ž—p•¨—�Šw‰ïŠw�p�u‰‰‰ï�u‰‰—\�e�W","Œö‰vŽÐ’c–@�l ‰ž—p•¨—�Šw‰ï","Vol. 2022.2","No. 0","pp. 1175-1175",2022,July
"Keisuke Kawahara,Keisuke Kawahara,Joe Sawada,Takumi Kamo,Yohtaro Umeda,Kyoya Takano","A 50 Gbps 49 mW CMOS Analog Multiplexer for a DAC Bandwidth Tripler",,"2022 IEEE Radio and Wireless Symposium (RWS)",,,,,2022,Jan.
"Keisuke Kawahara,Keisuke Kawahara,Yohtaro Umeda,Kyoya Takano","A Broadband Active Balun with Inductor-Less Active Peaking and Imbalance Correction",,"2021 IEEE International Midwest Symposium on Circuits and Systems (MWSCAS)",,,,,2021,Aug.
"Keisuke Kawahara,Keisuke Kawahara,Yohtaro Umeda,Kyoya Takano","Design of an Area-Efficient Differential Distributed Amplifier Based on the Theory of Differential Transmission Lines",,"2021 IEEE International Symposium on Circuits and Systems (ISCAS)",,,,,2021,May
"Keisuke Kawahara,Keisuke Kawahara,Yohtaro Umeda,Kyoya Takano","40 Gbps 180 nm CMOS Modulator Driver Using Loss Compensation Gain Cells",,"2020 IEEE International Symposium on Radio-Frequency Integration Technology (RFIT)",,,,,2020,Sept.