Resonant mode conversion in a dual-channel waveguide

Abstract

The even and odd modes resonant conversions are investigated in waveguides with the longitudinal periodic modulation. In the single channel potential well, mode conversion with the equal parity occurs. Under a dual-channel waveguide, the mode conversions with the equal parity occur in the two channels. Especially in the case of an asymmetric double potential well, new properties emerge. The results show that mode conversions of even- and odd-parity can be achieved simultaneously in the two channels respectively, which is distinct from the single and the symmetric double potential wells. Besides, the effects of nonlinearities on the conversion process are investigated. The results show that the nonlinearities causes a shift in resonance frequency, matching of frequency offset can improve the conversion effects obviously.