一种混合型石墨烯表面等离子体波导

A hybrid graphene surface plasmonic waveguide

针对光学元件存在体积大、带宽窄和损耗大的问题,提出一种适用于光电子集成电路的石墨烯波导结构。利用表面等离子体构成的波导结构能够突破衍射极限,可将光限制在亚波长范围内进行操控。同时石墨烯化学势的改变会影响波导的传输性能,实现波导的可调性,而不需要调整波导的几何形状。数值仿真表明,在工作波长1.55μm和化学势0.8eV情况下,基模的最小模式面积仅为0.003 4μm2,传播长度达到66.5μm。这种波导在纳米光子器件领域具有巨大的潜力。

Aiming at the narrow bandwidth and large loss of the existing bulky optical elements, a graphene waveguide structure is proposed for optoelectronic integrated circuit. The waveguide structure has the potential of confining optical field down to sub-wavelength range beyond the diffraction limit. The change of the chemical potential of graphene affects the transmission characteristics of waveguide which achieves tunable waveguide without the geometry adjustment. Numerical re sults reveal that the minimum mode area of 0. 003 4 μm^2 and the propagation length of 66.5μm are obtained at the wavelength of 1.55 μm and chemical doping of 0.8 eV. The waveguide provides a great potential in nanophotonics devices.