First principle study of molecular quantum dot cellular automata using mixed valence compounds

摘要

Quantum dot Cellular Automata (QCA) is one of the major paradigm shifts in the field of nanoscale computing. Among various QCA alternatives, molecular QCA claims to have extremely high device density along with room temperature fabrication advantage. In a molecular QCA the quantum dots are formed within the redox centers of a molecule and columbic interaction between the molecules form the QCA network. In the proposed work a molecular four-dot QCA cell has been designed using a mixed-valence compound. A c/oso-hexaborate structure has been utilized to form the central molecule along with the four corner molecules responsible for forming the four dots. The corner molecules are observed to have a resonating characteristic. The counterion effect of the proposed mixed-valence compound is responsible for the formation of the QCA cell. The counterion effect is verified using combined DFT and NEGF studies revealing the charge localization at the two diagonal dots, which is the fundamental property of a QCA cell.