Breaking Down Diamonds, Atom By Atom

An inadvertent breakthrough in laser technology could enhance the development of quantum computers and other diamond-based technologies.

Researchers at Macquarie University’s MQ Photonics Research Centre discovered that UV laser light was able to remove single atoms, one by one, from diamonds.

While working on the development of diamond lasers, the team made the find when the devices revealed erosion on the surface of the diamond facets that was destroying the beams’ optical path.

The atoms are released when the UV laser hits the diamond surface. Courtesy of Chris Baldwin.

This was not demonstrated with the UV laser light. Instead, the researchers manipulated single carbon atoms in diamonds, which are known to be very strongly bonded.

Until now, such manipulation has been done with sharp microscopic needles and found to be successful in materials with loosely bonded, easily moveable atoms, said Richard Mildren, associate professor at Macquarie. “Lasers are known to be very precise in cutting and drilling materials on a small scale, but on the atomic scale they have notoriously poor resolution,” he said.

Heat generation has historically limited the ability of lasers to make small, precise cuts. With UV lasers, this is not the case. The researchers have been able to influence atoms to draw structures in diamonds to about the size of a molecule, about 10 to 20 nm, and at higher resolutions.

A UV laser beam on synthetic diamond. Courtesy of Macquarie University Photonics Research Centre.

“The exciting thing is it opens up this possibility of manipulating some materials on much smaller dimensions than possible previously,” Mildren said. “If we can harness lasers at higher resolutions the opportunities at the atomic level are tremendous, especially for future nanoscale devices in data storage, quantum computers and nanosensors.”

The researchers will continue to study exactly what is occurring when the diamond material is broken down atom by atom. They are also looking at whether this process could be applicable to other materials as well.

The work is published in Nature Communications.

For more information, visit www.mq.edu.au.