All-optical method of developing some fundamental and functional quaternary logic gates

All optical multivalued logic processors are of paramount importance in optical computing and signal processing. In this article the author proposes a method of developing all-optical quaternary Inversion, NOT and Bitswap logic gates, which are essential parts of quaternary arithmetic and logical processors. Nonlinear switching and add/drop multiplexing (ADM) properties of semiconductor optical amplifier (SOA) are exploited here to develop the frequency encoded quaternary logic gates.