Control of plasmonic nanoantennas by reversible metal-insulator transition

Abstract

We demonstrate dynamic reversible switching of VO 2 insulator-to-metal transition (IMT) locally on the scale of 15a €‰nm or less and control of nanoantennas, observed for the first time in the near-field. Using polarization-selective near-field imaging techniques, we simultaneously monitor the IMT in VO 2 and the change of plasmons on gold infrared nanoantennas. Structured nanodomains of the metallic VO 2 locally and reversibly transform infrared plasmonic dipole nanoantennas to monopole nanoantennas. Fundamentally, the IMT in VO 2 can be triggered on femtosecond timescale to allow ultrafast nanoscale control of optical phenomena. These unique features open up promising novel applications in active nanophotonics.