Petronijevic Emilija, Larciprete Maria Cristina, Centini Marco, Pronti Lucilla, Aglieri Vincenzo, Razzari Luca, Toma Andrea, Macaluso Roberto, Voti Roberto Li, Sibilia Concita
Department SBAI, Sapienza University of Roma, Via A. Scarpa 14, 00161, Rome, Italy.
National Laboratories of Frascati - INFN, Via Enrico Fermi 54, 00044, Frascati, Rome, Italy.
Sci Rep. 2024 Oct 25;14(1):25324. doi: 10.1038/s41598-024-75430-0.
VO is a promising phase change material offering a large contrast of electric, thermal, and optical properties when transitioning from semiconductor to metallic phase. Here we show that a hybrid metamaterial obtained by proper combination of a VO layer and a nanodisk gold array provides a tunable plasmonic gap resonance in the infrared range. Specifically, we have designed and fabricated a metal-insulator-metal gap resonance by inserting sub-wavelength VO film between a flat gold layer and a gold nanodisk resonator array. The resonance of the hybrid metamaterial is centered in the useful 3-5 μm range when VO is in its semiconductor state. The experimental study highlights a monotonical spectral tuning of the resonance when increasing temperature up to 50 °C above the room temperature, providing a continuous resonance shift of almost 1 μm in the mid-infrared range. Wavelength range and intensity tunability can be further optimized by modifying the thicknesses of the layers and metamaterial parameters.
VO是一种很有前景的相变材料，当从半导体相转变为金属相时，它在电学、热学和光学性质上具有很大的对比度。在此我们表明，通过VO层和纳米盘金阵列的适当组合获得的混合超材料在红外范围内提供了可调谐的等离子体间隙共振。具体而言，我们通过在平坦金层和金纳米盘谐振器阵列之间插入亚波长VO薄膜，设计并制造了一种金属-绝缘体-金属间隙共振。当VO处于半导体状态时，混合超材料的共振集中在有用的3-5μm范围内。实验研究突出了在温度升高至比室温高50°C时共振的单调光谱调谐，在中红外范围内提供了近1μm的连续共振位移。通过改变层的厚度和超材料参数，可以进一步优化波长范围和强度可调谐性。
