Integration of Plasmonic Nanoheaters for Rapid and Tunable Light‐Driven Phase Transitions in VO₂ Nanocomposites

Abstract The synthesis, and characterization of vanadium dioxide (VO₂) nanopowders mixed with gold nanoparticles (AuNP) are presented, enabling phase transition under visible light illumination at ambient temperature via AuNP plasmonic heating. The inclusion of AuNP enhances the thermal sensitivity of VO₂, allowing precise control of its metal‐insulator transition (MIT). The MIT behavior is analyzed using Fourier transform infrared (FTIR) spectroscopy in the mid‐infrared spectrum under varying external light power densities. VO₂ nanoparticles are synthesized with different AuNP particle number ratios, ranging from 1:5 to 1:20. The illumination power density threshold for MIT ranges from 3.7 to 7.9 mW mm − 2 , depending on the particle ratio. Time‐resolved analysis of VO 2 reveals a two‐stage process, with rise times of 40 and 250 ms, and fall times of 12 and 140 ms, respectively. This rapid thermal response enables efficient phase modulation, achieving frequencies up to 1 kHz and a modulation depth of 10%.