A Beam-Propagation Method Using Both Electric and Magnetic Fields

The power evaluation in the beam-propagation method is reconsidered to overcome the problem that the power is not conserved during the propagation process. The Fresnel equations based on the electric and magnetic fields are solved in parallel, and both fields are employed for the power expression based on the Poynting vector. A spot-size and a polarization converter with a high-index contrast are analyzed and discussed.