Efficient computation of electromagnetic fields in arbitrarily-shaped, inhomogeneous dielectric bodies using transpose-free QMR and FFT

We present an alternative and more efficient method for computing electromagnetic fields in arbitrarily-shaped, inhomogeneous dielectric bodies. In this method, a transpose-free quasi-minimal residual (TFQMR) algorithm is employed to avoid the complicated multiplication between the transpose of the system matrix and a vector, resulting in a much simpler computer implementation. Moreover, the number of FFTs is reduced to only six per iteration. It is observed that the TFQMR-FFT method yields excellent results even for highly inhomogeneous dielectric objects.