Robust 1.7- m, all-polarization-maintaining femtosecond fiber laser source based on standard telecom fibers

We demonstrate a compact 1.7- m all-polarization-maintaining ultrafast fiber laser source, which employs soliton self-frequency shift in an optical fiber as the dominant spectral-shifting mechanism. The laser generates stable pulses with 384 fs pulse width and 102 MHz repetition rate centered at 1.7 m with 7 nm spectral bandwidth. The average power is about 35 mW with a high conversion efficiency of 66%. The measured root mean square output power stability over 10 h is as low as 0.22%. Both experimental and simulation results demonstrate that this laser has a potential to improving multiphoton imaging depth.