Daylight-Induced Metal-Insulator Transition in Ag-Decorated Vanadium Dioxide Nanorod Arrays

Abstract

Metal-insulator transition (MIT) in strongly correlated electronic materials has enormous potential with scientific and technological impacts in future oxide nano electronic devices. Although photo-induced MIT can provide opportunities to extend the novel functionality of strongly correlated electronic materials, there have rarely been reports on it. Here, we report MIT provoked by visible near-infrared light in Ag-decorated VO2 nanorod arrays (NRs) because of localized surface plasmon resonance (LSPR) and its application to broadband photodetectors. Our simulation results based on the finite-difference time-domain method show that the electric field resulting from LSPR can be generated at the interface between Ag nanoparticles and VO2 layers under vis NIR illumination. Using high-resolution transmission electronic microscopy and Raman spectroscopy, we observe the MIT and structural phase transition in the Agdecorated VO2 NRs due to the LSPR effect. The optoelectronic measurements confirm that high, fast, and broad photoresponse of Ag-decorated VO2 NRs is attributed to photo-induced MIT due to LSPR. Our study will open up a new strategy to trigger MIT in strongly correlated electronic materials through functionalization with plasmonic nanoparticles and serve as a valuable proof of concept for next-generation optoelectronic devices with fast response, low power consumption, and high performance.