The effect of wavefront tilt on mode conversion in asymmetrical Y-branch waveguides

Step approximation models provide a simple method of studying mode propagation and mode conversion in planar Y-branch optical waveguides. They are, however, only applicable to small branching angles since they neglect the wavefront tilt of the separating waveguides. A phasefront tilt approximation which can be used in conjunction with the local normal mode profile of the five-layer structure is introduced. By rotating the Y-branch about the branching point, a symmetrical branching angle is defined so that the phasefront approximation can be used not only for symmetrical Y-branches, but also for Y-branches which have an asymmetrical branching angle or have a change in branching angle along the longitudinal axis of the Y-branch. >

[1]  G. Betts,et al.  Crossing-channel waveguide electrooptic modulators , 1986 .

[2]  Hermann A. Haus,et al.  Coupled-mode theory of optical waveguides , 1987 .

[3]  E. Marom,et al.  Symmetric directional coupler switches , 1986 .

[4]  M. Miyagi,et al.  Wide Y-junctions with low losses in three-dimensional dielectric optical waveguides , 1985, IEEE Journal of Quantum Electronics.

[5]  Yaron Silberberg,et al.  Analysis of mode separation in multichannel branching waveguides , 1987 .

[6]  William K. Burns,et al.  Mode conversion in planar-dielectric separating waveguides , 1975 .

[7]  M. Feit,et al.  Comparison of calculated and measured performance of diffused channel-waveguide couplers , 1983 .

[8]  Leon McCaughan,et al.  A multiple scattering interaction analysis of intersecting waveguides , 1987 .

[9]  W. Chang,et al.  Extinction ratio degradation due to asymmetry in zero-gap directional coupling and crossing channel switches , 1987 .

[10]  P. Danielsen,et al.  Two-dimensional propagating beam analysis of an electrooptic waveguide modulator , 1984 .

[11]  Hiroshi Hirai,et al.  Analysis of single-mode optical Y-junction by the bounded step and bend approximation , 1988 .

[12]  M. Kuznetsov,et al.  Radiation loss in dielectric waveguide Y-branch structures , 1985 .

[13]  J. Cartledge,et al.  Towards the optimization of dielectric branching waveguides: the effect of longitudinal variations in the branching angle , 1988 .

[14]  Leon McCaughan,et al.  Novel physical effects in intersecting waveguides , 1987 .

[15]  N. Mikoshiba,et al.  Propagation characteristics of optical guided waves in asymmetric branching waveguides , 1981 .