Electronically configurable molecular-based logic gates

Logic gates were fabricated from an array of configurable switches, each co nsisting of a monolayer of redox-active rotaxanes sandwiched between metal electrodes. The switches were read by monitoring current flow at reducing v oltages, In the "closed" state, current flow was dominated by resonant tunn eling through the electronic states of the molecules. The switches were irr eversibly opened by applying an oxidizing voltage across the device. Severa l devices were configured together to produce AND and OR logic gates. The h igh and low current levels of those gates were separated by factors of 15 a nd 30, respectively, which is a significant enhancement over that expected for wired-logic gates.