Measurement of the third-order nonlinear refractive index of vanadium oxide nanoscrolls

Abstract

Vanadium dioxide is a strongly correlated electronic material which undergoes a phase transition from a semiconducting to metallic state when illuminated with an intense electric field. This phase transition marks interest in using VO2 as an optical limiter In this work, the z-scan method is used to find the third order nonlinear index n2 of VOx nanoscrolls prepared via a sol-gel method and then suspended in a liquid. The nonlinear index is then compared to the third order nonlinear index of multi-wall carbon nanotubes (also suspended in a liquid), and gold nanoparticles implanted in glass. Both the VOx nanoscrolls and multi-wall carbon nanotubes have similar n2, while the gold nanoparticles exhibit a much larger nonlinear index.