Method of single expression-advanced powerful tool for computer modelling of wavelength scale nonuniform frequency-selective 1D photonic structures

Main principles of the method of single expression (MSE) for boundary problems solution in classical electrodynamics are presented. In the MSE the solution of the Helmholtz´s equation is presented in the special form of a single expression. As a consequence, attained liberty from the obligation of the superposition principle permits to solve both linear and nonlinear problems with the same ease. In the MSE the Helmholtz´s equation is reformulated to the set of first order differential equations and the boundary problem is solved numerically. Using the MSE steady-state boundary problems are investigated for wavelength scale multilayer and modulated 1D photonic structures including loss, amplification and nonuniformity evoked by intense electromagnetic field.