All-optical adder/substractor using dark-bright soliton conversion control

We propose a new design of most important logical circuits using optical devices for all-optical addition/subtraction applications, in which the simultaneous operation of addition/subtraction arithmetic operation can be performed by using the dark-bright soliton conversion control. In operation, all-optical data input for addition/subtraction of binary operation logic `0' and `1' are formed by dark soliton (D) and bright soliton (B) pulses, respectively. By using the dark-bright soliton conversion behavior, the conversion between dark and bright soliton pulses can be obtained and form the logic pulses by a π/2 phase shifted device (i.e. an optical coupler), in which the binary operation can be formed simultaneously at the through and drop ports, respectively. In application, the proposed scheme can be recognized as a simple and flexible system for forming the logic switching system, which can be used for advanced logical system.