High Kerr nonlinearity of water in THz spectral range

Abstract

The values of the nonlinear refractive index coefficient for various materials in the terahertz frequency range exceed the ones in both visible and NIR ranges by several orders of magnitude. We report the direct measurement of the nonlinear refractive index coefficient of liquid water by using the Z-scan method with broadband pulsed THz beam. Our experimental result shows that nonlinear refractive index coefficient in water is positive and can be as large as 3.5$\times$10${}^{-10}$ cm${}^2$/W in the THz frequency range, which exceeds the ones for the visible and NIR ranges by 6 orders of magnitude.

arXiv comment7 pages, 3 figures

References in corpus (2)

• THz-pump -- THz-probe spectroscopy of semiconductors at high field strengths
• Self-phase modulation of a single-cycle terahertz pulse by nonlinear free-carrier response in a semiconductor

Cited by in corpus (4)

• Two-Dimensional Terahertz Spectroscopy of Condensed-Phase Molecular Systems
• Terahertz Nonlinear Index Extraction via Full-Phase Analysis
• Controlling the water nonlinear refractive index in the THz frequency range via temperature variation
• Temperature-independent non-linear terahertz transmission by liquid water