Quantum sensing of the resistive switching in a Mott insulator thin-film device
We used a nanoscale thermometer coupled to a defect engineered device based on the Mott insulator VO2 to measure the device temperature as it switches from the insulating to the metallic state. Using the temperature dependence of the microwave absorption as measured by photoluminescence of an NV-center placed directly on the switching region, we found that pristine VO2 switches only when it reaches the transition temperature whereas ion-irradiated VO2 devices can switch with negligible change in temperature. The non-thermal transition in ion-irradiated devices is therefore much more energy efficient than the Joule-heating-driven transition. See also Highly Energy-Efficient Resistive Switching.