The Robust QCA Adder Designs Using Composable QCA Building Blocks

Quantum-dot cellular automata (QCA) is attracting a lot of attention due to its extremely small feature size and ultralow power consumption. Up to now, several adder designs using QCA technology have been proposed. However, it was found that not all of the designs function properly. This paper analyzes the reasons of the failures and proposes adders that exploit proper clocking schemes