Measurement of the third order nonlinear susceptibility of paratellurite single crystal using multiplex CARS

Zakaniaina Rajaofara,Philippe Leproux,Jean-René Duclère,Philippe Thomas,Vincent Couderc,Hideaki Kano,Erwan Capitaine,Tomokatsu Hayakawa

doi:10.1063/1.5113478

Abstract

We report the extraction of the real part of the third order nonlinear susceptibility for a c-cut paratellurite (TeO2 − α) single crystal using the nonresonant contribution of the multiplex coherent anti-Stokes Raman scattering (M-CARS) signal. Using fused silica and SF57 as nonlinear reference materials, we derive the absolute value of the real part of the electronic third order susceptibility and we evidence the in-plane modulation of the nonlinear refractive index. These results are in total agreement with those recently obtained by the z-scan method.

Highlights

The coherent Raman anti-Stokes scattering (CARS) technique has been commonly used for microscopy applications thanks to its wide ability to probe the vibrational resonances of biological samples
multiplex coherent anti-Stokes Raman scattering (M-CARS) vibrational signatures are accompanied by an additional nonlinear signal called nonresonant background (NRB), which is provided by the electronic response of the matter
In this paper we present the extraction of the real part of the electronic response Re[χN(3R)(ω)] of a c-cut TeO2 − α single crystal by considering the NRB of M-CARS spectra

Summary

Introduction

The coherent Raman anti-Stokes scattering (CARS) technique has been commonly used for microscopy applications thanks to its wide ability to probe the vibrational resonances of biological samples. A. Armstrong et al in 1962.2 In its simplest configuration, CARS system is used to probe a single vibrational mode which is stimulated by the beating of two monochromatic synchronized waves called pump (ωp) and Stokes (ωs) waves. When the power density exciting the sample is sufficiently strong and the frequency difference between pump and Stokes waves matches that of a vibrational mode, a coherent response from the matter is observed. M-CARS vibrational signatures are accompanied by an additional nonlinear signal called nonresonant background (NRB), which is provided by the electronic response of the matter. The NRB is coherent with the vibrational signal and strongly modulates the total CARS intensity which is given by the Eq 1:7

Methods

Results

Conclusion