Computational fidelity in reversible quantum-dot cellular automata channel routing under thermal randomness

The computational fidelity is the measure, which imposes the knowledge about how far any noisy computational channel resembles the accurate output for the distribution of the same input. The logical operations and signalpropagation through semiconductor quantum-dot cellular automata (QCA) having different cell's polarization are affected with environmental noise such as thermal randomness. This paper outlines the computational fidelity in reversible QCA channel routing for noiseless, as well as noisy reversible QCA channels. To show the fidelity for reversible QCA channels, QCA based Feynman gate, Fredkin gate, Peres gate and Toffoli gate have been assumed as a reversible routing channels. Shannon's theory has been applied to measure the fidelity, which confirms the robustness in reversible QCA channel routing. The temperature range at which reversible QCA channels yield trustworthy computation is proposed in this article. It is established that the computational fidelity of the routing channels deteriorates with thermal randomness. On an average, those routing channels have reliable fidelity when perform computation in between 1K to 10K temperatures. Hence, all the routing channels yield considerable computational fidelity over the low thermal regions. The evaluation of theoretical values through simulation results establishes the design accuracy for the proposed reversible QCA routing channels.