Masahiro Nada, Fumito Nakajima, Shoko Tatsumi, Yuki Yamada, Yasuhiko Nakanishi, Toshihide Yoshimatsu, Kimikazu Sano, Hideaki Matsuzaki. Inverted p-down pin photodiode exceeding 70-GHz bandwidth featuring low operating bias voltage of 2 V. In European Conference on Optical Communications, ECOC 2020, Virtual Event, Belgium, December 6-10, 2020. pages 1-4, IEEE, 2020. [doi]