Alternative approach of developing all-optical Fredkin and Toffoli gates

• Reversible logic gates show potential roles in communication technology.
• The authors propose three-input–output Fredkin and Toffoli gates.
• Frequency conversion property of SOA is exploited.
• Optical multiplexers and de-multiplexers are used for beam routing.

Reversible logic gates show potential roles in communication technology, and it has a wide area of applicability such as in sequential and combinational circuit of optical computing, optical signal processing, multi-valued logic operations, etc. because of its advantageous aspects of data-recovering capabilities, low power consumption, least power dissipation, faster speed of processing, less hardware complexity, etc. In a reversible logic gate not only the outputs can be determined from the inputs, but also the inputs can be uniquely recovered from the outputs. In this article an alternative approach has been made to develop three-input–output Fredkin and Toffoli gates using the frequency conversion property of semiconductor optical amplifier (SOA) and frequency-based beam routing by optical multiplexers and demultiplexers. Simulation results show the feasibility of our proposed scheme.