Background-free broadband CARS spectroscopy from a 1-MHz ytterbium laser

We introduce a novel configuration for broadband, time-resolved CARS spectroscopy/microscopy in which pump, Stokes and probe pulses are all derived from a single femtosecond Yb:KYW laser. The 1-MHz repetition rate of the system allows very intense CARS signals to be obtained over short acquisition times, while a delayed probe pulse ensures an efficient non-resonant background suppression.