Illustration of the coralyne-intercalated DNA junction used to create a single-molecule diode, which can be used as an active element in future nanoscale circuits. (Credit: Ben-Gurion University)

Engineers are struggling to shrink the silicon used in processors to power increasingly smaller computing hardware and are rapidly reaching the point where silicon’s performance starts to degrade due to its size. To move beyond the material’s physical limitations, researchers at Ben-Gurion University of the Negev in Israel and the University of Georgia, Athens, have discovered how to use a single molecule of DNA to create the world’s smallest diode, which controls the flow of electricity by allowing it to travel in just one direction.

The researchers created the diode from a specially designed piece of a single, duplex DNA. The strand was an 11 base pair piece of DNA that was connected to a nanoscale electronic circuit.

In early trials, the current flowing through the DNA strand exhibited no unusual behavior. But, the team discovered that, after adding a molecule called coralyne into the test substance, the piece of DNA began to act like a diode.

The researchers say that nanoscale circuits could transform the field of electronics, leading to the production of electronic components more than 1,000 times smaller than what is currently in the market.