NUMERICAL STUDY OF ELECTROMAGNETIC-WAVE PROPAGATION IN TWISTED BIREFRINGENT LAYERS BY THE SPECTRAL MOMENTS METHOD

This paper presents a first attempt at using the spectral moments meth od (SMM) to solve Maxwell's equations in twisted anisotropic media in the presence of defects. This numerical method, previously developed i n condensed matter physics, allows computation of Green functions for very large systems. The dynamic matrix of the discretized system is bu ilt from the medium parameters. Green functions, calculated for a give n source, representing a point source at infinity and given receiver, are developed as a continued fraction whose coefficients are related t o the moments and directly computed from the dynamic matrix. In this s tudy we compute the light transmitted through thin surface-stabilized ferroelectric liquid crystal cells with a chevron structure and a twis ted director distribution. The efficiency and accuracy of the method a re analysed by comparing the results obtained by SMM with the analytic al solution obtained using the Jones matrix formalism. Finally, we app ly SMM to compute the transmitted light with different director config urations. We show, by comparisons with experimental data, that the sim plest director configuration is certainly the most probable.