Two-dimensional materials hold a great promise for developing extremely fast, compact and inexpensive optoelectronic devices. A molybdenum disulphide (MoS₂) monolayer is an important example which shows strong, stable and gate tunable optical response even at room temperature near excitonic transitions. However, optical properties of a MoS₂monolayer are not documented well. Here, we investigate the electric field effect on optical properties of a MoS₂ monolayer and extract the dependence of MoS₂ optical constants on gating voltage. The field effect is utilised to achieve ~10% visible light modulation for a hybrid electro-optical waveguide modulator based on MoS₂. A suggested hybrid nanostructure consists of a CMOS compatible Si₃N₄ dielectric waveguide sandwiched between a thin gold film and a MoS₂ monolayer which enables a selective enhancement of polarised electro-absorption in a narrow window of angles of incidence and a narrow wavelength range near MoS₂ exciton binding energies. The possibility to modulate visible light with 2D materials and the robust nature of light modulation by MoS₂ could be useful for creation of reliable ultra-compact electro-optical hybrid visible-light modulators.

二维材料为开发极其快速，紧凑和廉价的光电器件提供了广阔的前景。二硫化钼（MoS ₂）单层是一个重要的例子，即使在室温下接近激子跃迁的情况下，它也显示出强大，稳定和可门可调的光学响应。然而，MoS ₂单层的光学性质没有被很好地证明。在这里，我们研究了电场对MoS ₂单层光学特性的影响，并提取了MoS ₂光学常数对门控电压的依赖性。场效应用于基于MoS ₂的混合电光波导调制器实现约10％的可见光调制。建议的混合纳米结构由夹在金薄膜和MoS ₂单层之间的CMOS兼容Si ₃ N ₄电介质波导组成，该单层能够在狭窄的入射角窗口和附近的窄波长范围内选择性增强极化电吸收MoS ₂激子结合能。利用2D材料调制可见光的可能性以及MoS ₂进行光调制的强大特性对于创建可靠的超紧凑型电光混合可见光调制器可能很有用。