Adaptive multilevel beam propagation method

A beam propagation method (BPM) with an adaptive discretization of a 1D cross section and a longitudinal step-size control is presented. In contrast to most approaches to a BPM that use an a priori fixed grid for the numerical discretization of the transversal optical field, the algorithm presented generates a space grid during the simulation depending on the geometry of the structure and on the actual computed field solution. In general, such an adaptively generated grid is highly nonuniform. An automatic stepsize control is introduced to complete the adaptive concept.<
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