Fast tunable all-polarization-maintaining supercontinuum fiber laser for CARS microscopy

We have demonstrated a compact fiber laser with broad and fast wavelength tunability for coherent anti-Stokes Raman scattering (CARS) microscopy. Originated from an Er-doped fiber laser, the Stokes pulses can be tuned from 1015 to 1060 nm within 300 μs from supercontinuum of a tapered high nonlinear fiber, while pump pulses at 790 nm were obtained by second harmonic generation. The two beams were then sent to microscopes for CARS detection of oil, ethanol and mouse ear samples. This fast and broadly tunable fiber laser in the all-polarization-maintaining architecture would be promising to implement rapid label-free histology in clinical translation.