We generate broadband pulses covering the Yb: and Tm:silica amplification ranges with a passively phase-locked front end based on Er:fiber technology. Full spectral coherence of the octave-spanning output from highly nonlinear germanosilicate bulk fibers is demonstrated. Seeding of a high-power Tm:fiber generates pulses with a clean spectral shape and a bandwidth of 50 nm at a center wavelength of 1.95 μm, pulse energy of 250 nJ, and repetition rate of 10 MHz.
© 2012 Optical Society of America
Original Manuscript: November 9, 2011
Revised Manuscript: December 23, 2011
Manuscript Accepted: December 23, 2011
Published: February 8, 2012
Sören Kumkar, Günther Krauss, Marcel Wunram, David Fehrenbacher, Umit Demirbas, Daniele Brida, and Alfred Leitenstorfer, "Femtosecond coherent seeding of a broadband Tm:fiber amplifier by an Er:fiber system," Opt. Lett. 37, 554-556 (2012)