Thermal induced tunability of surface plasmon resonance in Au-VO2 nano-photonics

A new class of nano-photonics for possible χ3(ω) applications have been synthesized by pulsed laser ablation and optically characterized. Compared to standard nano-composites exhibiting an exalted effective χ3(ω) due to the enhancement of the local electric field, these Au-VO2 nano-composites display an additional reversibly tunable surface plasmon frequency under external temperature stimuli. This is due to the semi-conducting/metallic first order transition of the host VO2 matrix. The nano-gold surface plasmon wavelength shifts reversibly from 645 to 598 nm when the Au-VO2 nano-composites temperature varies from 25 to 120 °C. Even if the spectral shift is not extensively large, such a tunability is positively genuine.