Thermally Tunable Ultra-Broadband Terahertz Metasurface Absorber Based on VO2 Phase Transition
5 affiliations
- 1College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
- 2Shenzhen Key Laboratory of Micro-Nano Photonic Information Technology, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, THz Technical Research Center of Shenzhen University, Shenzhen University, Shenzhen 518060, China
- 3Department of Electrical Engineering, College of Engineering in Wadi Addawasir, Prince Sattam Bin Abdulaziz University, Al-Kharj 11991, Saudi Arabia
- 4Department of Electrical Engineering, College of Engineering, King Saud University, Riyadh 11421, Saudi Arabia
- 5Department of Electrical Engineering, College of Engineering, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11432, Saudi Arabia
Abstract
Vanadium dioxide (VO2), owing to its reversible insulator-to-metal phase transition, is a promising material for tunable terahertz (THz) devices. In this work, a compact VO2-based terahertz absorber is numerically proposed to achieve thermally tunable ultra-broadband absorption. The proposed single-layer metasurface employs a fourfold-symmetric integration of cross-shaped, circular-ring, and square-frame elements to induce multiple coupled resonances and their spectral overlap, providing a design strategy for broadening the absorption bandwidth while maintaining polarization-insensitive operation. The optimized structure exhibits five near-perfect absorption resonances at 3.23, 5.27, 7.34, 8.82, and 9.73 THz. At a VO2 conductivity of 2.0 × 105 S/m, the absorber achieves absorptance exceeding 90% from 2.95 to 10.36 THz, corresponding to a bandwidth of 7.41 THz and a relative bandwidth of 111.35%. The absorption mechanism is attributed to the hybridization of multiple resonant modes and effective impedance matching with free space, as confirmed by electromagnetic field and impedance analyses. Furthermore, the absorption response can be dynamically tuned through the phase transition of VO2. The absorber also exhibits polarization-insensitive behavior and maintains high absorptance over a wide range of incident angles. These results demonstrate a compact and thermally reconfigurable platform for terahertz imaging, sensing, spectroscopy, and adaptive electromagnetic stealth.
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BibTeX
@article{ali2026thermally,
title = {{Thermally Tunable Ultra-Broadband Terahertz Metasurface Absorber Based on VO2 Phase Transition}},
author = {Ahmed Ali and Hamid Sharif and Asrafali Barkathulla and Wazie M. Abdulkawi and Majeed A. S. Alkanhal and Yosef T. Aladadi},
journal = {Nanomaterials},
year = {2026},
month = oct,
doi = {10.3390/nano16201293},
url = {https://www.mdpi.com/2079-4991/16/20/1293},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Thermally Tunable Ultra-Broadband Terahertz Metasurface Absorber Based on VO2 Phase Transition
AU - Ahmed Ali
AU - Hamid Sharif
AU - Asrafali Barkathulla
AU - Wazie M. Abdulkawi
AU - Majeed A. S. Alkanhal
AU - Yosef T. Aladadi
PY - 2026
DA - 2026/10/01
JO - Nanomaterials
DO - 10.3390/nano16201293
UR - https://www.mdpi.com/2079-4991/16/20/1293
AB - Vanadium dioxide (VO2), owing to its reversible insulator-to-metal phase transition, is a promising material for tunable terahertz (THz) devices. In this work, a compact VO2-based terahertz absorber is numerically proposed to achieve thermally tunable ultra-broadband absorption. The proposed single-layer metasurface employs a fourfold-symmetric integration of cross-shaped, circular-ring, and square-frame elements to induce multiple coupled resonances and their spectral overlap, providing a design strategy for broadening the absorption bandwidth while maintaining polarization-insensitive operation. The optimized structure exhibits five near-perfect absorption resonances at 3.23, 5.27, 7.34, 8.82, and 9.73 THz. At a VO2 conductivity of 2.0 × 105 S/m, the absorber achieves absorptance exceeding 90% from 2.95 to 10.36 THz, corresponding to a bandwidth of 7.41 THz and a relative bandwidth of 111.35%. The absorption mechanism is attributed to the hybridization of multiple resonant modes and effective impedance matching with free space, as confirmed by electromagnetic field and impedance analyses. Furthermore, the absorption response can be dynamically tuned through the phase transition of VO2. The absorber also exhibits polarization-insensitive behavior and maintains high absorptance over a wide range of incident angles. These results demonstrate a compact and thermally reconfigurable platform for terahertz imaging, sensing, spectroscopy, and adaptive electromagnetic stealth.
SN - 2079-4991
ER -