The TM mode in the self‐focusing dielectric planar waveguide

Abstract

AbstractThe TM0 guided mode in the self‐focusing dielectric planar waveguide and its universal dispersion curves are obtained by an approximation method, The single mode propagation condition of the fundamental mode TE0 in the self‐focusing planar waveguide is discussed based on the cutoff wavelengths of the higher‐order TE modes and the higher‐order TM modes. The coupling between the fundamental mode TE0 and the second mode TM0 is described by the calculation of the birefringence between the TE0 mode and the TM0 mode. It was found that the Kerr effect with α > 0 (α is a parameter which describes the film nonlinearity) causes the fields to be confined in the self‐focusing film, which results in the waveguide wavelength decreasing and the cutoff wavelength increasing as α is increased. In addition, the range of the single mode propagation is increased as α is increased. If the self‐focusing planar waveguide can support both the TE0 mode and the TM0 mode, then the coupling between the TE0 mode and the TM0 mode is very strong and can be decreased by increasing α. © 1992 John Wiley & Sons, Inc.