Design and fabrication of frequency-responsive terahertz transmittance modulator based on vanadium dioxide spherical films
| Autor: | Tianyu Su, Jiran Liang, Zhang Ke, Shuangli Wang, Xuan Yu |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Materials science
Frequency band business.industry Terahertz radiation Resonance 02 engineering and technology Sputter deposition 021001 nanoscience & nanotechnology 01 natural sciences Atomic and Molecular Physics and Optics Electronic Optical and Magnetic Materials 010309 optics Dipole Optics Electric field 0103 physical sciences Transmittance Electrical and Electronic Engineering Physical and Theoretical Chemistry 0210 nano-technology Absorption (electromagnetic radiation) business |
| Zdroj: | Optics Communications. 488:126834 |
| ISSN: | 0030-4018 |
| Popis: | In this paper, a spherical film array structure based on vanadium dioxide (VO2) was designed and fabricated aimed to enhance the frequency response of transmittance in terahertz (THz) band of VO2 films. Vanadium dioxide and vanadium pentoxide composite spherical films were grown on the surface of two-dimensional single layer array of SiO2 sphere by magnetron sputtering and rapid thermal annealing method, and the frequency response of transmittance of spherical films was studied. The THz transmittance modulation depth (MD) of spherical films increased significantly in the 1.5–3 THz range as frequency increased, while MD of planar films only increased slightly throughout the frequency band. We attributed the frequency response of the MD of spherical films to the absorption by electric dipole resonance. The numerical simulations and electric field distributions illustrate that the regulating effect of resonance absorption would increase as the width of spherical gaps increase. When the width of the spherical gaps was 0 . 05 μ m , the absorptivity would increase by 120% from 1.5 to 3 THz, showing the possibility of further improving the THz MD of spherical films. This research would provide a good candidate material in the active modulation in terahertz band which broaden a path for dynamic terahertz radiation manipulation devices. |
| Databáze: | OpenAIRE |
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