Three input NAND gate using quantum dot semiconductor optical amplifier.

The work describes design and simulations of a three input NAND gate using quantum dot semiconductor optical amplifiers for the first time as far as author's knowledge goes. Both cross gain modulation and cross phase modulations implement the NAND operation in a modified manner. Amplitude modulation, extinction ratio, relative eye opening, contrast ratio, etc. are optimized in terms of control power and their dependence on amplified spontaneous noise has been investigated for three different unsaturated gains of the QDSOA. These parameters show efficient performance for unsaturated gains 20 and 30 dB. REO value more than 99% and Q value more than 16 dB ensure practical feasibility of the logic gate proposed. [ABSTRACT FROM AUTHOR]