title: Optical net gain measurement in n-type doped germanium waveguides under optical pumping for silicon monolithic laser.
abstract: Silicon (Si) monolithic lasers are key devices in large-scale, high-density photonic integrated circuits. Germanium (Ge) is promising as an active layer due to the complementary metal-oxide semiconductor process compatibility with Si. A net optical gain from Ge is essential to demonstrate lasing operation. We fabricated Ge waveguides and investigated the n-type doping effect on the net optical gain. The estimated net gain of the n-Ge waveguide increased from -2200 to -500/cm, namely reducing loss, under optically pumped condition.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Okumura
authors.forename: Katsuya
authors.initials: K
authors.lastname: Oda
authors.forename: Junichi
authors.initials: J
authors.lastname: Kasai
authors.forename: Misuzu
authors.initials: M
authors.lastname: Sagawa
authors.forename: Yuji
authors.initials: Y
authors.lastname: Suwa