The iPhones and Android devices of a decade or two from now could be a million times more powerful than the ones on the market, thanks to research being done at Ben-Gurion University, in conjunction with the University of Georgia.

A joint Israel-US team has built the first “molecular diode,” an electrical conductor that was built out of a single DNA molecule, constructed from 11 base pairs – the smallest such component ever built, and a milestone in the emerging field of molecular electronics.

“We are still at the very beginning of this, but our work has demonstrated that electricity can be conducted through a molecular component – meaning that we could eventually build transistors that would let us put a million more transistors and components into the same form factors we have today,” said Dr. Yoni Dubi of the Department of Chemistry at Ben-Gurion University. “There are very few research labs in the the world that can do this, but now that we have demonstrated that it is possible, the next step is to try it on other components, with the goal building molecular-sized transistors and switches, among other things.”

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Diodes are the second-most common component – after transistors – in electrical devices, and in fact are themselves building blocks of transistors (diodes are made of two layers of silicon, transistors three, and both are components of semiconductors). Diodes act as “gateways,” with electrical current running through them (either conducting the flow to a component, or blocking it, depending on how it is constructed).

In the BGU-UG experiment (the University of Georgia component was led by Prof. Bingqian Xu of the school’s College of Engineering), researchers took a DNA molecule constructed from 11 base pairs (much smaller than “standard” DNA molecules; a DNA strand has 3.2 billion base pairs), and connected it to an electronic circuit only a few nanometers large.

“The reason we used DNA molecules has nothing to do with the fact that they are organic, but because there are a lot of tools available for the manipulation of DNA that have been in use for decades already,” said Dubi. “DNA manipulation tools offer the best opportunity for scientists to work at the nano level.”

When they measured the current through the molecule, the researchers found that the molecule did not show any special behavior. However, when the DNA was intercalated with a molecule named coralyne, the behavior of the circuit changed drastically – now, the current was 15 times larger for negative voltages than for positive voltages, a necessary feature for a diode. The researchers deduced that they had created a diode composed of a single DNA molecule.

With the principle now proven – and the method to transmit electrical current through molecular-sized particles now established – the next step is to move on to other components, said Dubi.

“We want to perfect this device and make it more efficient, and try it on more devices,” said Dubi. “We can try it on switches and other components of semiconductors and chips. Because these components can be so small, many more of them can be stuffed into the same sized devices we have today – making them far more powerful than what we know today. It may take ten years, or it may take 50 years, but it is definitely on the way. We can’t even imagine what these devices are going to look like.”