Energy Exchange at Degenerate Mixing of Four Fast TE 2 Modes of a Thin Left-Handed Film on a Nonlinear Substrate

Frequency-degenerate mixing of forward and backward propagating fast modes is considered in a planar optical waveguide based on a thin left-handed film and a right-handed substrate exhibiting the Kerr effect. Nonlinear coupled-mode equations are solved for the intensities of these modes in the neglect of the contributions of elementary processes that fail to satisfy the phase-matching condition. It is shown that the intramode self-action of four TE modes is accompanied by energy exchange between these modes. The efficiency of energy exchange varies periodically along the propagation direction of modes, thus leading to the inversion of the intensities of forward and backward propagating light fields on the interaction half-period.