Researchers created a switch from a single molecule

The group of researchers for the first time demonstrated a single-molecular electret, a device that can be one of the keys to creating molecular computers. Nature Nanotechnology reports about the new development.

Smaller electronics are crucial for the development of more advanced computers and other devices. The scientists are looking for a way to replace silicon chips with molecules. Of course, this includes the development of a single-molecular electret, a switching device that could serve as a platform for extremely small non-volatile storage devices. However, experts were confident in the instability of such a device and generally wondered if it would ever be invented.

And yet, together with international colleagues, Mark Reed, professor of electrical engineering and applied physics, demonstrated a single-molecular electret with functional memory.

Most of the electrets are made from piezoelectric materials, such as those that reproduce sound in speakers. In an electret, all dipoles – pairs of opposite electric charges – spontaneously line up in one direction. By using an electric field, you can change their direction.

“It was always a question of how small these electrets, which are essentially storage devices, could be,” Reid explains.

The researchers inserted a gadolinium atom (Gd) inside a carbon buckyball, a 32-sided molecule also known as bamminsterfullerene. When scientists placed this structure in a transistor-type structure, they saw the transfer of a single electron and used this to understand its energy state. The real breakthrough was the discovery that an electric field could be used to switch the energy state from a stable state to some other.

“This molecule acts as if it had two stable polarization states,” Reid explains.

Reid emphasized that the existing structure of the device is currently not applicable to any device, but proves that molecular science has a lot to develop for application in technology.

“We have proved that it is possible to create two states in a molecule that cause spontaneous polarization and two switchable states,” concludes the study author. “And this can lead to new ideas. For example, to compress memory literally to a single molecular level. Now that we understand that this is possible, we can move on to new developments”.