Thermal Conductivity of VO2 Nanowires at Metal-Insulator Transition Temperature

Vanadium dioxide (VO2) nanowires endowed with a dramatic metal-insulator transition have attracted enormous attention. Here, the thermal conductance of VO2 nanowires with different sizes, measured using the thermal bridge method, is reported. A size-dependent thermal conductivity was observed where the thicker nanowire showed a higher thermal conductivity. Meanwhile, the thermal conductivity jump at metal-insulator transition temperature was measured to be much higher in the thicker samples. The dominant heat carriers were phonons both at the metallic and the insulating regimes in the measured samples, which may result from the coexistence of metal and insulator phases at high temperature. Our results provide a window into exploring the mechanism of the metal-insulator transition of VO2 nanowires.

Automated summary

This study reported the size-dependent thermal conductivity of vanadium dioxide nanowires, revealing that thicker nanowires exhibit higher thermal conductivity and a more significant thermal conductivity jump at the metal-insulator transition temperature. Phonons were identified as the dominant heat carriers in both metallic and insulating regimes, possibly due to the coexistence of metal and insulator phases at high temperatures.