Binary encoding via electrostatic coupling — wire propagation and majority gate
QCA cells encode binary information in the position of two electrons among four quantum dots (corners of a square). Coulomb repulsion drives electrons to opposite corners. Polarization P = ±1 encodes 0/1. Information propagates at the speed of light through electrostatic coupling — no current flow needed. A 3-input majority gate computes M(A,B,C) = AB+BC+CA. Proposed for post-CMOS computing at molecular scale.