Thermochromic and Femtosecond-Laser-Induced Damage Performance of Tungsten-Doped Vanadium Dioxide Films Prepared Using an Alloy Target

Thermochromic tungsten-doped VO(2) thin films were successfully fabricated using a W-V alloy target. X-ray diffraction analyses showed that the W-doped VO(2) film had a preferred orientation of (011), and that the doping did not degrade the film crystallinity compared with that of the pure film. X-ray photoelectron spectroscopy and energy-dispersive spectroscopy showed that the doped 0.81 atom% tungsten replaced vanadium in the lattice of the film. The metal–insulator transition temperature of the W-doped VO(2) film was reduced to 35.5 °C, which is close to room temperature. Additionally, the infrared transmittance modulation of the W-doped film at λ = 2500 nm reached 56%, indicating an excellent switching efficiency. The damage behavior of the W-doped VO(2) film under a femtosecond-laser irradiation was experimentally investigated. Our results revealed that defect-related damages induced by the femtosecond laser are relevant for W-doped VO(2) films. This study provides valuable insights into VO(2) films for potential applications in laser protection.