Analysis of X-Intersecting Waveguide Switches with a Large Branching Angles Ranging from 2° to 12°

Abstract

This is a study on the analysis of the X-junction waveguide switches with a large branching angle ranging from 2° to 12°. The characteristics of the modeled are simulated by using the beam propagation method. We will show that, for an X-intersecting waveguide with a branching angle more than 2°, the eigenmodes interference remains and prevails even up to 12°. This produces a high unbiased crosstalk. In the analysis of the modulation efficiency of the switch, it is revealed that a large positive refractive index change will produce higher modulation efficiency than a negative refractive index change because of optical field re-distribution. In designing an X-intersecting waveguide switch using the coupled mode theory, a -40 dB crosstalk can be achieved for device smaller than 2 µ m. The interference X-intersecting waveguide switches will be more suitable for large scale switching arrays.