Tuning the Dielectric Constant Zero Crossing of Vanadium Dioxide (VO 2 )

Vanadium Dioxide (VO 2 ) has a metal-to-insulator phase transition (MIT) near 68°C. Drastic changes in electrical and optical properties of VO 2 are observed at this temperature. We have found that thin films of VO 2 have epsilon-near-zero (ENZ) regions in the near infrared that can be thermally tuned over nearly 1000 nm by exploiting this phase transition. They may also show potential for enhanced Kerr response in this ENZ region.