Bonding and Antibonding Modes in Metal–Dielectric–Metal Plasmonic Antennas for Dual‐Band Applications

• DOI: 10.1002/adom.201900942
• Publication Date: 2019-08-17T03:15:18Z
• Authors: Kateryna L. Domina; Vyacheslav V. Kha...; Vitaliy Goryashko; Alexey Y. Nikitin
• Keywords: Antibonding molecular orbital

Abstract Resonant optical antennas supporting plasmon polaritons (SPPs)—collective excitations of electrons coupled to electromagnetic fields in a medium—are relevant sensing, photovoltaics, and light‐emitting devices, among others. Due the SPP dispersion, conventional antenna fixed geometry, exhibiting narrow resonance, cannot simultaneously operate two different spectral bands. In contrast, here it is demonstrated that metallic disks, separated by nanometric spacer, hybridized antibonding mode stays visible range, while bonding one can be pushed down mid‐infrared range. Such an dimer sense materials nanoscale volumes, whose fingerprint central frequencies differ factor 5. Additionally, resonance tuned employing phase‐change material (VO 2 ) as spacer. The dielectric constant controlled heating at frequency mode. These findings open door new class optoelectronic devices able significantly ranges linear regime, with same polarization illuminating wave.