Fiber-Based High-Energy Femtosecond Pulses Tunable From 920 to 1030 nm for Two-Photon Microscopy

We demonstrate a fiber-based femtosecond laser source, which can deliver 37 MHz, ~100 fs laser pulses tunable from 920 nm to 1030 nm with up to 10 nJ pulse energy. Pumped by an ultrafast Yb-doped fiber laser, a short piece of tapered photonic crystal fiber with lower dispersion was used to generate self-phase-modulation filtered for the tunable pulses. We believe that this new type of high-energy ultrafast fiber laser source can be an ideal solution for the two-photon fluorescence microscopy applications.