Demonstration of the evanescent Kerr effect in optical nanofibers

Abstract

Optical nanofibers have recently emerged as attractive nanophotonic platforms for many applications ranging from quantum technologies to nonlinear optics, due to both their tight optical confinement and their wide evanescent field. Herein we examine both theoretically and experimentally the optical Kerr effect induced by the evanescent field of a silica nanofiber surrounded by different nonlinear liquids such as water, ethanol and acetone and we further compare them with air cladding. Our results show that the evanescent Kerr effect significantly dominates the usual Kerr effect into the silica core for sub-wavelength diameters below 560 nm, using acetone. We further report the observation of the evanescent Kerr effect through surrogate measurements of stimulated Raman-Kerr scattering (SRKS) in an acetone-immersed silica nanofiber. Our findings open the way towards potential applications of optical nanofibers to ultra-sensitive liquid sensing or to enhancing the nonlinear effects through the evanescent field.

Polarization of Brillouin scattered light in silica nanofibers

“…The acoustic wavevector matches the wave vectors difference between the two cross-polarized optical modes supported by the birefringent fibers [9][10]. Since backward Brillouin scattering in ONFs features both longitudinal L0m and torso-radial TR21 modes, we may expect similar effects in a slightly birefringent nanofiber [4].…”

“…Silica optical nanofibers (ONF) are very attractive nanophotonic platforms for many applications such as optical sensing and nonlinear photonics due to both their wide evanescent field and the tight field confinement in the waist region [1][2][3][4]. It has been further shown that ONFs possess unique elastic properties owing to the strong coupling between shear and longitudinal acoustic waves [5].…”

Conception and reproducibility study of efficient evanescent Raman converters based a nanofiber immersed in a liquid

“…In the sub-nanosecond regime, as the effective length of interaction and the pump length are of the same magnitude ( ~ 10 𝑐𝑚), backward nonlinear effects can be favored [13]. On OSA2, we observed backward Raman scattering, neither in silica nor in ethanol.…”

Laser-Induced Damage in Silica Nanofibers in Air and Immersed in Different Liquids in the Nanosecond Regime

“…This property has been exploited for optical sensing [2] or optical traps for quantum applications [3]. The excitation of optical nonlinearities such as Stimulated Raman Scattering (SRS) [4] or Kerr effect in the evanescent field of nanofibers immersed in liquids has also been demonstrated [5].…”