Tile-Based QCA Design Using Majority-Like Logic Primitives

The design of circuits and systems in Quantum-dot Cellular Automata (QCA) is still in infancy. The basic logic primitive in QCA is the majority voter (MV), that is not a universal function; so, inverters (INV) are also required. Blocks (referred to as tiles) are utilized in this article. A tile with a combined logic function of MV and INV (MV-like function) is proposed. It is shown that the MV-like tile can be effectively used in logic design as basic primitive. Tiles based on both the fully populated (FP) and non-fully populated (NFP) grids are investigated in detail. Various arrangements in inputs and outputs are also possible among the 4 sides of a grid, thus defining different tiles. Using a coherence vector simulation engine, it is shown that the 3 × 3 grid offers versatile logic operation. Different combinational functions such as majority-like and wire crossing are obtained using these tiles. Tile-based design of different circuits is compared to gate-based and SQUARES designs.