In this letter, the mixed finite element method (Mixed FEM) incorporating with the surface current boundary condition (SCBC) is firstly proposed to perform eigenmode numerical simulations of graphene-based plasmonic waveguides. The SCBC which is based on modeling graphene as the zero-thickness conductive sheet, is introduced to reduce the extremely fine discretization of graphene at the atomic scale. Thus, enormous unknowns and computational resources are significantly decreased in the proposed new method. Numerical examples of some typical graphene-based waveguides are presented to verify numerical accuracy and computational efficiency of the new method.

中文翻译：

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通过具有表面电流边界条件的混合 FEM 对基于石墨烯的等离子体波导进行建模

在这封信中，首次提出了结合表面电流边界条件 (SCBC) 的混合有限元方法 (Mixed FEM) 来执行基于石墨烯的等离子体波导的本征模式数值模拟。引入基于建模石墨烯作为零厚度导电片的 SCBC，以减少石墨烯在原子尺度上的极细离散化。因此，在所提出的新方法中，大量的未知数和计算资源显着减少。给出了一些典型的基于石墨烯的波导的数值例子，以验证新方法的数值精度和计算效率。