Theoretical analysis of wavelength response and electrode optimization for SOA based optical inline detector

The wavelength response of 1.55 mu m Near Traveling Wave Semiconductor Optical Amplifier(NTWSOA) based optical inline detector is reported in this paper. Three schemes of detection viz, single full length electrode, short single electrode and differential electrode are compared. Optimization of the electrode length and position in the case of differential electrode has provided significant improvement in the detection voltage and responsivity than the other schemes. The short single length electrode detection scheme provides better linearity characterstics than the other two schemes, along with a nominal value of detection voltage and responsivity. The optimum differential detection scheme, is found to provide an improvement of 6.98dB and 7.05 dB for 1550 nm and 1560 nm respectively compared to single short length elctrode scheme. It also provides 22.44 dB and 21.6 dB improvement in detected voltage compared to full length electrode detection scheme respectively, at -10 dBm input power.