Muhammad Faryad, Akhlesh Lakhtakia, Peter Monk, Manuel Solano:
Comparison of rigorous coupled-wave approach and finite element method for photovoltaic devices with periodically corrugated metallic backreflector
Optimal design of photovoltaic devices with a periodically corrugated metallic backreflector requires a rapid and reliable way to simulate the optical characteristics for wide ranges of wavelength and angle of incidence. Two independent numerical techniques are needed for confidence in numerical results. We compared the rigorous coupled-wave approach (RCWA) and the finite element method (FEM), the former being fast and flexible, but the latter having predictable convergence even for discontinuous constitutive properties. Depending on the shape of the corrugation and the constitutive properties of the metal and dielectric materials making up the device, both methods can exhibit slow convergence rates for p-polarized light. The chosen model problem in this paper is of this type. As rapid spatial variations of the fields are the underlying cause, suitable selective refinement of the FEM mesh can overcome this slow convergence. Therefore, it would be desirable to have a self-adaptive scheme for choosing the mesh in the FEM. This will slow down the algorithm, but will give a reliable way to check the RCWA results.
This preprint gave rise to the following definitive publication(s):
Muhammad FARYAD, Akhlesh LAKHTAKIA, Peter MONK, Manuel SOLANO: Comparison of rigorous coupled-wave approach and finite element method for photovoltaic devices with periodically corrugated metallic backreflector. Journal of the Optical Society of America A, vol. 31, 10, pp. 2275-2284, (2014).