In this vein, a new range of molecule-sized devices have been created in the laboratory, though with varying results in terms of efficiency and practicality. Now a group of researchers from Berkeley Lab and Columbia University claims to have created the highest-performing, single-molecule diode ever made, which is said to be 50 times better in performance and efficiency than anything previously produced.

Ordinary diodes are usually constructed from silicon with a p-n (positive-negative) junction created at the point of contact between a positively "doped" semiconductor (that is, one that has had its electrical properties altered with additives) and a negatively doped one. Flanked by connecting electrodes (an anode on one side and a cathode on the other), the most common function of such a diode is to permit electric current to flow in one direction only, whilst blocking current from flowing in the reverse direction.