A TM Y-branch wavelength multi/demultiplexer by K/sup +/ and Ag/sup +/ ion-exchange for /spl lambda/=1.31 and 1.55 /spl mu/m

A Y-branch multi/demultiplexer by K/sup +/ and Ag/sup +/ ion-exchange was optimally designed, using the 2-D beam propagation method (BPM) and successfully fabricated for /spl lambda/=1.31 and 1.55 /spl mu/m. The measured extinction ratios of our preliminary devices are about 20 dB.