title: Nonlinear-microscopy optical-pulse sources based on mode-locked semiconductor lasers.
abstract: We developed picosecond optical-pulse sources suitable for multiphoton microscopy based on mode-locked semiconductor lasers. Using external-cavity geometry, stable hybrid mode locking was achieved at a repetition rate of 500 MHz. Semiconductor optical amplifiers driven by synchronized electric pulses reached subharmonic optical-pulse repetition rates of 1-100 MHz. Two-stage Yb-doped fiber amplifiers produced optical pulses of 2 ps duration, with a peak power of a few kilowatts at a repetition rate of 10 MHz. These were employed successfully for nonlinear-optic bio-imaging using two-photon fluorescence, second-harmonic generation, and sum-frequency generation of synchronized two-color pulses.
authors.affiliation: New Industry Creation Hatchery Center, Tohoku University, Aoba-ku, Sendai, Japan. yoko@niche.tohoku.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Yokoyama
authors.forename: A
authors.initials: A
authors.lastname: Sato
authors.forename: H-C
authors.initials: HC
authors.lastname: Guo
authors.forename: K
authors.initials: K
authors.lastname: Sato
authors.forename: M
authors.initials: M
authors.lastname: Mure
authors.forename: H
authors.initials: H
authors.lastname: Tsubokawa