ANALYSIS OF 3-LINE TAPERED VELOCITY COUPLERS WITH A NONLINEAR WAVE-GUIDE

We investigate a three-waveguide tapered velocity coupler which consis ts of a uniform linear, tapered linear and tapered nonlinear slab wave guide. The coupling characteristics depending on the gap width between the waveguides and sloping angle of the tapered waveguides are analyz ed by means of the finite difference method. The numerical results sho w that with realistic structural parameters flat output power characte ristics can be obtained over a wide range of input power. It is found that it is possible to use the present structure as a power limiter.