Department of Mechanical Engineering, Columbia University , New York, New York 10027, United States.
Nano Lett. 2015 Mar 11;15(3):2001-5. doi: 10.1021/nl504860z. Epub 2015 Mar 2.
Nanoscale and power-efficient electro-optic (EO) modulators are essential components for optical interconnects that are beginning to replace electrical wiring for intra- and interchip communications.1-4 Silicon-based EO modulators show sufficient figures of merits regarding device footprint, speed, power consumption, and modulation depth.5-11 However, the weak electro-optic effect of silicon still sets a technical bottleneck for these devices, motivating the development of modulators based on new materials. Graphene, a two-dimensional carbon allotrope, has emerged as an alternative active material for optoelectronic applications owing to its exceptional optical and electronic properties.12-14 Here, we demonstrate a high-speed graphene electro-optic modulator based on a graphene-boron nitride (BN) heterostructure integrated with a silicon photonic crystal nanocavity. Strongly enhanced light-matter interaction of graphene in a submicron cavity enables efficient electrical tuning of the cavity reflection. We observe a modulation depth of 3.2 dB and a cutoff frequency of 1.2 GHz.
纳米级、低功耗的电光（EO）调制器是光互连的关键组件，它们开始取代用于芯片内和芯片间通信的电布线。1-4 基于硅的 EO 调制器在器件占地面积、速度、功耗和调制深度方面具有足够的优异性能。5-11 然而，硅的弱电光效应仍然是这些器件的技术瓶颈，这促使人们开发基于新材料的调制器。石墨烯，一种二维碳同素异形体，由于其出色的光学和电子特性，已成为光电应用的替代有源材料。12-14 在这里，我们展示了一种基于石墨烯-氮化硼（BN）异质结构与硅光子晶体纳米腔集成的高速石墨烯电光调制器。在亚微米腔中，石墨烯的强光物质相互作用使腔反射的电调谐变得高效。我们观察到 3.2 dB 的调制深度和 1.2 GHz 的截止频率。
