講演情報
[23p-21B-8]Tunable Transmittance of Silicon Nanofilms by Transverse-Electric Graphene Surface Plasmon Polaritons in THz regime
〇(PC)Yunhui WU1, Yury KOSEVICH2, Jose ORDONEZ-MIRANDA1,3, Kazuhiro HIRAKAWA1, Sebastian VOLZ1,3, Masahiro NOMURA1,3 (1.IIS Univ. of Tokyo, 2.Russian Acad. Sci., 3.LIMMS Univ. of Tokyo)
キーワード：
graphene、plasmon、THz
Terahertz (THz) electromagnetic spectrum, ranging from 0.1 to 10 THz, has garnered significant attention due to its applications in sensing, imaging, and 5G/6G communication. Silicon owns its high transparency in the THz range and its seamless coupling with modern microelectronics. Theoretically, silicon can be tuned from highly transmissive to highly reflective by topping a monolayer graphene [1]. This transition is due to the coupling of transverse-electric graphene surface plasmon polariton (TE-SPP) with THz radiation. However, this phenomenon has never been observed experimentally.
In this work, we experimentally demonstrate the tuning of the transmittance of a 200-nm-thick silicon film with a topped monolayer graphene. We measured its transmission with a Fourier Transfer Infrared (FTIR) in the THz range and found that the transmittance of silicon nanofilm was reduced by more than 20% at 2.5 THz due to the presence of TE-SPP, which well-agreed with our theoretical model. Based on this finding, we explore furthermore the influence of Si nanofilm thickness, graphene layer quality, and incident THz frequency on this tunability. The obtained results thus shed light on the fundamental interactions between plasmon polaritons and nanoscale dielectrics to control and tune their optical properties driving the performance of reconfigurable THz devices.
In this work, we experimentally demonstrate the tuning of the transmittance of a 200-nm-thick silicon film with a topped monolayer graphene. We measured its transmission with a Fourier Transfer Infrared (FTIR) in the THz range and found that the transmittance of silicon nanofilm was reduced by more than 20% at 2.5 THz due to the presence of TE-SPP, which well-agreed with our theoretical model. Based on this finding, we explore furthermore the influence of Si nanofilm thickness, graphene layer quality, and incident THz frequency on this tunability. The obtained results thus shed light on the fundamental interactions between plasmon polaritons and nanoscale dielectrics to control and tune their optical properties driving the performance of reconfigurable THz devices.