In this work, we propose a graphene-based electro-absorption modulator design using an asymmetric plasmonic slot waveguide. Such asymmetric slot waveguide allows us to achieve a strong light-matter interaction with a large orientation match between the polarization of confined modal field and graphene plane. Thus, a significant change in total optical absorption and, hence, modulation efficiency is achieved over a small active interaction length. The modulation efficiency is further enhanced by employing double-layer graphene and using both of them as tunable absorber. Reduced interaction length also lowers the device capacitance, which allows realizing compact devices with switching energy as low as 86.45 aJ/bit and modulation bandwidth over 1 THz for a 3 dB device length of 1.6 μm at an operating wavelength of 1550 nm.

在这项工作中，我们提出了使用非对称等离子缝隙波导的基于石墨烯的电吸收调制器设计。这种不对称的缝隙波导使我们能够在有限的模态场和石墨烯平面的极化之间实现大的方向匹配，从而实现强烈的光-物质相互作用。因此，在较小的主动相互作用长度上，总的光吸收发生了显着变化，从而实现了调制效率。通过使用双层石墨烯并将它们都用作可调吸收体，可以进一步提高调制效率。减小的相互作用长度也降低了器件电容，从而允许实现紧凑型器件，其开关能量低至86.45 aJ / bit，调制带宽超过1 THz，在1550 nm的工作波长下具有1.6μm的3 dB器件长度。