▎ 摘　　要

This paper reports two design thoughts about nano-scale waveguides including parallel slot structure and vertical slot structure. According to the simulation results of different schemes, the design of parallel slot structure is demonstrated to exhibit better performance. Thus, we further explore its typical characteristics based on this scheme, such as electric field distribution, effective refractive index, non-linearity, dispersion and so on. Besides, we explore the properties of the waveguide under different thicknesses of the core material. On the other hand, combining with graphene layer applied to additional bias voltage, the tunable properties of the waveguide are realized. These results can provide significant reference for photoelectronic device field and lead to a deeper insight of the physical mechanisms of graphene-based waveguides.