Q-switched mode-locking femtosecond all-fiber laser based on Er ~(3+)/Yb~(3+) codoped phosphate fiber

摘要

A Q-switched mode-locking femtosecond all-fiber laser based on a 2 cm long homemade Er~(3+)/Yb~(3+) codoped phosphate glass fiber has been reported. By using the nonlinear polarization evolution technique, a nearly 100% modulation depth of mode-locking pulse train is achieved. At a pump power of 410 mW, the energy of each Q-switched envelope, whose width is about 220 μs, is 10 μJ, while the duration of mode-locking pulse within the Q-switched envelope is 318-fs.