Transient gain from N2+ in light filaments

  title={Transient gain from 
 in light filaments},
  author={Ladan Arissian and Brian Kamer and Ali Asghar Rastegari and David Villeneuveand Jean Claude Diels},
  journal={Physical Review A},
We perform high resolution spectroscopy of $N_2^+$ emission in light filaments using a controlled pump at 795 followed by a second harmonic weak probe. Our result suggests that transient gain is achieved by resonant stimulated Raman scattering. 

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