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Title: Terahertz nonlinear index extraction via full-phase analysis

We experimentally show the spectrally averaged nonlinear refractive index and absorption coefficient for liquid water, water vapor,α<#comment/>-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 nonlinear index of7.8×<#comment/>10−<#comment/>10cm2/Wand6×<#comment/>10−<#comment/>11cm2/W, respectively, which are both much larger than expected.

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Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optics Letters
0146-9592; OPLEDP
Page Range / eLocation ID:
Article No. 5628
Medium: X
Sponsoring Org:
National Science Foundation
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