Modulation of the laser-induced phase transition of VO2/W-TiO2 n-n heterojunction

To solve the contradiction between the low phase transition threshold and the infrared switching efficiency (r) of VO2, the VO2/W-TiO2 n-n heterojunction was fabricated on the K9 glass substrate with the magnetron sputtering. The effects of W doping for TiO2 layer on the heterojunction phase transition performance were investigated. An appropriate W doping increases the carrier concentration (n) and its mobility (μ), thereby reducing both the thermotropic phase transition threshold (Tc) and the laser-induced phase transition threshold (Pc) of the heterojunction. The heterojunction doped 1.37 at% W exhibits the optimal comprehensive performance. The r of the heterojunction is up to 56.8%, the Tc decreases to 54.3 °C, and the Pc to 51.8 W/cm².