Lossless stripe waveguide optical beam splitter: modeling of the Y-structure

We present a theoretical model of a loss-compensated symmetric Y-junction acting as an optical beam splitter. We consider silica (SiO/sub 2/) channel waveguides which are assumed to be highly doped with Er/sup 3+/. The model was developed using the beam propagation method (BPM) and a fast-Fourier-transform (FFT)-based algorithm. The analysis showed that considerable gain levels, about 4.2 dB/cm at each port of the Y-junction, can be achieved for erbium concentration 2.5/spl times/10/sup 20/ ions/cm/sup 3/, signal power 1 /spl mu/W and pump power 250 mW.