Experimental Demonstration of Optical XOR and XNOR based on Polarization Interference

In this paper, polarization interference between two lights carrying binary signals is used to realize logic functions. Direct detection is adopted to obtain the corresponding logic output. By setting the power of the input signals, the bias levels, and the polarization rotation angle of the two lights, different optical logic gates can be realized within the same hardware setup. In the experiments, XOR and XNOR are successfully realized at the data rate of 1Gbit/s. Simulations are further carried out to optimize the setup and analyze system performance under the influence of some key factors such as input power, extinction ratio (ER) of modulators.