Bulletin of ANPA

Abstract submitted to ANPA Conference July 14–16, 2023

Volume 5, Number 1

Atomic, Molecular, Optical and Plasma Physics
Abstract ID: ANPA2023-N00024

Abstract:

ANPA2023-N00024: Polarity of Nonlinear Refraction coefficient in Graphene-Oxide Monolayer through SSPM

Authors:

  • Tikaram Neupane; Department of Chemistry and Physics, The University of North Carolina at Pembroke, Pembroke, NC 28372
  • Riley S. Edwards; Department of Chemistry and Physics, The University of North Carolina at Pembroke, Pembroke, NC 28372, U.S.A.
  • Xander A. Vasquez Amores;

The study on the polarity and magnitude of nonlinear refraction (NLR) coefficient of the graphene-oxide (GO) atomic layer is of great interest for optoelectronic applications. It is studied through the laser-induced spatial self-phase modulation (SSPM) of an optical field which reveals the nonlinear refraction coefficients of GO atomic layers in an aqueous base solution with a resonant excitation using a chopped quasi-static laser at 532 nm. It displayed several concentric diffraction rings at the far field due to the laser-induced intensity-dependent refractive index in the materials (GO). The formation of concentric diffraction rings is due to the coherent superposition of transverse wave vectors. The number of concentric rings as a function of the applied intensity revealed the nonlinear refraction coefficient of GO which was estimated to be ~-6.65×10^-12 m^2/W for the laser-excitation duration of ~0.32 sec., where the negative polarity of nonlinear refraction coefficient was confirmed with the interference image profile of SSPM. The upper and vertical distortion of concentric rings at the far-field at the longer laser-excitation duration of ~0.8 sec. indicates the distortion of the coherent superposition of transverse wave vectors due to the localized thermal vortex of GO in the aqueous solution that offers novel platforms of thermal metrology based on the localized optical nonlinearity and temperature-sensitive all-optical switching.

To cite this abstract, use the following reference: https://anpaglobal.org/conference/2023/ANPA2023-N00024