Quantum-dot cellular automata-based design for three-level nanoscale full-subtractor

Abstract

• A new approach to full-subtractor circuit design is proposed in this research. • The new design is built with XOR and majority gates, making it both efficient on the gate level and abstract. • This structure is created with a significant reduction in the number of cells and the amount of space used. • The QCADesigner-E tool is used for circuit design and verification, as well as for power analysis. Future digital devices and circuits can be frequently designed using quantum-dot cellular automata (QCA). High density and speed are good matches for QCA. As a result, a full subtractor is well suited for this technology. QCA can be utilized to create the full-subtractor at the nanoscale since it is a specific sort of circuit employed in important applications. A subtractor circuit can be created similarly to an adder circuit in electronics. When utilizing the traditional two's complement notation, subtractors are commonly implemented within a binary adder for a low cost by supplying an addition/subtraction selector to the carry-in and inverting the second operand. In this research, we present a new full-subtractor circuit construction. The XOR and majority gates, which work on the Columbic interaction of cells, are utilized for this purpose. QCADesigner-E is used to model and test the proposed structure's functionality. The full-subtractor architecture provides a platform for easier access to the input and output lines. This design is made using the multi-layer crossover approach and 22 QCA-based cells. The number of cells in the suggested structure has been improved by 31 percent, while the occupied area has been improved by 30 percent.