All optical Full-Adder and Full-Subtractor using Semiconductor Optical Amplifiers and All-Optical Logic Gates

Abstract

Optical Amplifiers have provided a more efficient robust and better alternative to design and integrate optical devices feasibly with traditional optical networks and systems for optical signal processing and optical communication networks. There are mainly three most common ways in which an optical amplifier may be used in an optical link. There are many types of optical amplifiers available one of which is the Semiconductor optical amplifier (SOA). The working of an SOA is just like that of a LASER, the only difference between a LASER and an SOA is that the later doesn’t have feedback mechanism as present in the case of former. Stimulated emission causes the amplification of entering light waves. An effect known as Cross phase modulation has been utilized in this work in order to exploit the non-linear properties of optical medium. Cross phase modulation takes place when two or more optical fields pass through the same optical medium simultaneously, the change in refractive index due to one optical field causes phase modulation of the other optical fields. This phenomenon is widely used to detect and study the non-linear properties of the link or the optical medium under consideration.In this work we have proposed schematics for full-adder and full-subtractor circuits. We have provided two separate circuit designs which has the schematic of Sum/Difference in the first one and Carry/Borrow in the second. Considering an input sequence of 10 bits we have simulated our schematic designs in OptiSystem 16 research software. The observations have been incorporated in the results section.