Demonstration of a functional quantum-dot cellular automata cell

We report an experimental demonstration of a functional cell for quantum-do t cellular automata (QCA), a transistorless approach to implement logic fun ctions. The four-dot QCA cell is defined by a pair of series-connected, cap acitively coupled input and output double dots. We demonstrate that, at low temperature, an electron switch in the input double dot induces an opposit e electron switch in the output double dot, resulting in a complete polariz ation change of the QCA cell. Switching is verified by electrometer signals which are coupled to the output double dot. Experimental results suggest t hat electron motion in the coupled double dots is Strongly correlated and c an support high operating frequencies. Agreement between theoretical predic tions and experimentally measured values of the dot potentials is excellent . (C) 1998 American Vacuum Society. [S0734-211X(98)13106-2].