Figure 2.

Tunable nanodisk metasurface model. (a) Normalized field confinement at the center of the VO₂ nanodisks in the insulating (in situ) phase, showing a spectral overlay of electric and magnetic dipole modes at 2020 nm and a higher-order magnetic resonance at 1630 nm. The field confinement in the metal (Met.) phase is shown as well. (b) Modeled spectrum of continuously tunable optical phase and (c) modeled spectrum of continuously tunable transmittance shown vs TuneFrac, from the dielectric phase to the metallic phase of VO₂. (d) Amplitude and phase modulation at the spectrally overlapping dipole mode (2020 nm). (e) Amplitude and phase modulation along the slope of the spectrally overlapping resonant modes show large amplitude change (−19 dB) with little residual optical phase change (35°). (f) Amplitude and phase modulation around the higher-order magnetic resonant mode (1676 nm) showed an optical phase tuning of 228° with little residual amplitude modulation (4 dB).