Visible optical nonlinearity of vanadium dioxide dispersions.

Vanadium dioxide (VO), a correlated oxide compound, is one of the functional materials extensively studied in solid state physics due to its attractive physical properties. However, the nonlinear optical response of VO and related all-optical applications have been paid less attention. Here, the nonlinear refractive index ( ) and third-order nonlinear susceptibility ( ) of VO dispersions have been acquired to be 3.06 × 10 cm W and 1.68 × 10 esu at a wavelength of 671 nm, and 5.17 × 10 cm W and 2.83 × 10 esu at a wavelength of 532 nm the spatial self-phase modulation (SSPM) and spatial cross-phase modulation (SXPM) effects in the visible regime, respectively. Based on the excellent nonlinear optical properties of VO dispersions, the proof-of-principle functions such as optical logic or-gates, all-optical switches, and inter-channel information transfer are implemented in the visible wavelength. The experimental results on the response time of VO to light indicate that the formation of diffraction rings is mainly an electronically coherent third-order nonlinear optical process. The experimental results show that the VO dispersions exhibit an excellent nonlinear optical response and may lay the foundation for the application of VO-based all-optical devices.