Conformal Coating of a Phase Change Material on Ordered Plasmonic Nanorod Arrays for Broadband All-Optical Switching

Abstract

Actively tunable optical transmission through artificial metamaterials holds great promise for next-generation nanophotonic devices and metasurfaces. Plasmonic nanostructures and phase change materials have been extensively studied to this end due to their respective strong interactions with light and tunable dielectric constants under external stimuli. Seamlessly integrating plasmonic components with phase change materials, as demonstrated in the present work, can facilitate phase change by plasmonically enabled light confinement and meanwhile make use of the high sensitivity of plasmon resonances to the variation of dielectric constant associated with the phase change. The hybrid platform here is composed of plasmonic indium-tin-oxide nanorod arrays (ITO-NRAs) conformally coated with an ultrathin layer of a prototypical phase change material, vanadium dioxide (VO), which enables all-optical modulation of the infrared as well as the visible spectral ranges. The interplay between the intrinsic plasmonic nonlinearity of ITO-NRAs and the phase transition induced permittivity change of VO gives rise to spectral and temporal responses that cannot be achieved with individual material components alone.

Tunable and reconfigurable metasurfaces and metadevices

“…When phase changes between two states, VO 2 is accompanied by significant changes in optical and electronic properties. It is a suitable functional material for many optoelectrical applications, such as active polarizer in near-infrared region 95 , tunable absorber 97,187,188 , tunable switching 189,190 , beam steering 191 , switchable quarter wave plate (QWP) in THz 96,192 , and active nanoantennas for tuning THz resonance [193][194][195] . By hybridizing metasurfaces with VO 2 , an ultrathin switchable THz QWP with a switching range of 34 GHz was experimentally demonstrated 96 .…”

Hydrothermal Synthesis of VO2 Polymorphs: Advantages, Challenges and Prospects for the Application of Energy Efficient Smart Windows

“…Various TCE materials, such as Ag nanowires, carbon nanotube, Al‐doped ZnO, ITO/FTO and graphene are incorporated with VO 2 to activate its thermochromic performance. Specially, as shown in Figure a–d, the electrothermochromic device combining VO 2 nanoparticles with ultra‐long Ag nanowires can regulate the infrared transmittance dynamically as the input voltage and action time change.…”

Multifunctional Hybrid Metasurfaces for Dynamic Tuning of Terahertz Waves

“…Hybrid metasurfaces can be dynamically tuned on demand by external stimuli, including carrier injection into the semiconductors, gate‐controlled graphene, phase transition of the phase‐change materials (PCMs), and electrically biasing the liquid‐crystal materials . Among them all, vanadium dioxide (VO 2 ) is particularly interesting as its intrinsic insulator‐to‐metal phase transition (IMT) is reversible through various external stimuli such as thermal heating, applied current, and optical pumping . Such ability endows VO 2 a fantastic candidate in electrically triggered and optical modulated hybrid metasurfaces.…”