A multilayer graphene-based optical modulator is proposed in this study. The structure is made of several layers of graphene on hexagonal boron nitride (hBN), working at 193 to 200 THz (1.5 to 1.55 μm) band. In this modulator, the electric field passes through graphene layers instead of passing through the silicon waveguide, causing very low insertion losses about 4 × 10 ^-3 dB for 40 μm long device. It is shown that the transverse magnetic mode has a more efficient propagation in the modulator. Due to the passage of light from graphene layers and the graphene's optical characteristics, light transmission can be controlled with less variation in gate voltage, and it has the better switching performance concerning monolayer, bilayer and diagonal graphene optical modulators.

中文翻译：

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hBN衬底波导调制器上的多层石墨烯

本研究提出了一种基于多层石墨烯的光调制器。该结构由六层氮化硼（hBN）上的多层石墨烯制成，工作在193至200 THz（1.5至1.55μm）的波段。在此调制器中，电场穿过石墨烯层而不是穿过硅波导，从而对于40μm长的器件造成非常低的插入损耗，约为4×10 ^-3 dB。结果表明，横向磁模在调制器中具有更有效的传播。由于来自石墨烯层的光的通过和石墨烯的光学特性，可以在栅极电压变化较小的情况下控制光传输，并且对于单层，双层和对角线石墨烯光学调制器，它具有更好的开关性能。