Y-branch - the key component for crosstalk reduced optical switches: modelling analysis

A novel design method for switching devices is demonstrated based on waveguide structures with Y-branches and abrupt waveguide changes as key elements. A combination of BPM calculation and eigenmode analysis is shown to be a promising tool to obtain deep insight into the physical mode behaviour. Based on the analysis, a mode converter to match the eigenmodes in amplitudes and phase can be developed and introduced as a correcting device. This method is demonstrated for the crosstalk compensation of a digital switch (DOS) and a Δβ-reversal switch. A crosstalk of about −20 dB can be reduced to −40 dB by this method. This revised version was published online in November 2006 with corrections to the Cover Date.