Asymmetric Cross-Shaped Optical Antennas with Wide Spectral Tunability and High Optical Cross-Sections

Abstract Resonant optical antennas (ROAs) are nanodevices that can enhance the electromagnetic field in their vicinity and scatter light far field. The enhanced is localized subdiffraction-limited volume. Their ability to exhibit strong enhancement gap makes them suitable for coupling with quantum emitters. This paper introduced two novel bimodal triple-modal asymmetric cross-shaped nanoantenna designs. performance of reported nanoantennas numerically studied via finite element method (FEM). electric enhancements cross-sections calculated characterize These low-symmetry polarization-sensitive devices. Furthermore, plasmonic nanostructures or three tunable resonances near-infrared wavelength regions ultra-high enhancement. coupled exhibits a 45.9 high-energy resonance 149.4 low-energy resonance, respectively, on $$\left|{E}_{\mathrm{TOT}}\right|/\left|{E}_{\mathrm{IN}}\right|$$ E TOT / IN scale.