Novel efficient fault-tolerant full-adder for quantum-dot cellular automata

Quantum-dot cellular automata (QCA) are an emerging technology and a possible alternative for semiconductor transistor based technologies. A novel fault-tolerant QCA full-adder cell is proposed: This component is simple in structure and suitable for designing fault-tolerant QCA circuits. The redundant version of QCA full-adder cell is powerful in terms of implementing robust digital functions. By considering two-dimensional arrays of QCA cells, fault tolerance properties of such block full-adder cell can be analyzed with misalignment, missing and dislocation cells. To verify the functionality of the proposed device, some physical proofs and computer simulations using QCADesigner are provided.  Both simulation results and physical relations confirm our claims and its usefulness in designing fault-tolerant digital circuits.