Simple approach to high-fidelity tunable narrow-band pulse generation.

Tunable narrow-band short-pulse coherent emission can be generated by the optical parametric amplification of a seeded continuous wave (CW) laser. However, the residual CW pedestal can affect the accuracy of the optical measurements and the exact interpretation of the experimental data. We demonstrate a simple approach to removing the residual CW seed in a frequency tunable, seeded parametric amplification setup in the nanosecond regime by adding an additional parametric amplification stage which is seeded by an idler wave from the first stage. We validate this method by using a pump-probe experiment in an atomic vapor. Our results show the elimination of an atomic vapor hyperfine pumping signal after the CW pedestal has been removed.