摘要
We demonstrate a fundamentally mode-locked Yb-fiber laser with 3 GHz repetition rate and ∼206 fs pulse duration. The laser incorporates two enabling technologies: a 1 cm heavily Yb-doped phosphate glass fiber as the gain medium and a high-dispersion (-1300 fs 2 ) output coupler to manage cavity dispersion. The oscillator self-starts and generates up to 53 mW average power. © 2012 Optical Society of America.