Field-based recovery technique for improved adaptive finite element analysis of photonic devices

A new adaptive finite element (FE) technique is proposed to enhance the accuracy of the solution of wave propagation in integrated photonic devices. The suggested recovery technique improves significantly the finite element convergence rate compared to refinement techniques. The method refines the elements based on the field distribution. This recovery technique estimates the error at each element by comparing the linear FE solution and the recovery solution using least-squares method. The numerical aspects and accuracy of the method are investigated using the light propagation in both one-dimensional and two-dimensional photonic devices.