Architecture for an external input into a molecular QCA circuit

A simple architecture for data input into a molecular quantum-dot cellular automata (QCA) circuit from an external CMOS circuit is proposed. A “T”-shaped interconnect, utilizing fixed-polarization cells to provide the desired polarization, is controlled via external electrodes connected to a standard CMOS input driver. The applied input signal is used to gate either the propagation of a fixed polarization, P=+1, or that of the complementary fixed polarization, P=−1, into the QCA circuit. The architecture utilizes the field-driven clocking scheme proposed in recent literature to achieve transduction between applied input voltage and a molecular configuration. The system is modelled using the coherence vector formalism with a three-state basis and simulated using the QCADesigner simulation tool.