Local thermal heating in VO$_2$ electric-field-induced metal insulator transition

Over recent years, the insulator to metal transition (IMT) of the vanadium dioxide (VO$_2$) Mott insulator has been revisited revealing an electric-field-induced resistance switching. Whether this feature is purely due to an electrical field effect or due to some Joule heating is still under debate. Here we report a local temperature measurement in a 10$\mu$m and a 20$\mu$m VO$_2$ junction while going through the resistance switching. The sample was placed at $\Delta$T=15K below 340K (the thermally induced insulator to metal transition). When ramping up the voltage across the junction we find that the local heating inside the VO$_2$ junction is close to 15K. This data suggests that in these temperature, current and voltage ranges, the field induced IMT can be explained by local Joule heating. Work supported by the French ANR-09-BLAN-0388-01 and the US DOE and AFOSR.