Terahertz nonlinear index extraction via full-phase analysis.

  title={Terahertz nonlinear index extraction via full-phase analysis.},
  author={Kareem J Garriga Francis and Mervin Lim Pac Chong and Yiwen E and X.-C. Zhang},
  journal={Optics letters},
  volume={45 20},
We experimentally show the spectrally averaged nonlinear refractive index and absorption coefficient for liquid water, water vapor, α-pinene, and Si using a full-phase analysis in the terahertz regime through a standard time-domain spectrometer. Our results confirm that the nonlinear index of refraction of the liquid samples in this regime exceeds the near-infrared optical nonlinear index by six orders of magnitude. In the case of liquid water and water vapor at atmospheric pressure, we find a… 
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