New lasers to take aim at just one atom
It may soon be possible to cut and drill materials one atom at a time, using a super-focused laser.
Lasers have often been considered a highly accurate device, but a nano-scale this has not been true – until now.
A newly discovery has shown that light can pick apart a substance atom by atom, creating new avenues for nano-scale diamond devices.
“Lasers are known to be very precise at cutting and drilling materials on a small scale – less than the width of a human hair, in fact – but on the atomic scale they have notoriously poor resolution,” says Macquarie University researcher Associate Professor Richard Mildren.
“If we can harness lasers at higher resolutions, the opportunities at the atomic level are tremendous, especially for future nano-scale devices in data storage, quantum computers, nano-sensors and high-power on-chip lasers.”
Currently, industrial lasers separate materials by super-heating the surface at the focal point of the beam. Although useful in industries such as in car manufacturing, this technology has severe limitations when addressing fabrication challenges in nano-devices.
Australian research colleagues Andrew Lehmann and Carlo Bradac have now discovered that it is possible to remove atoms from a surface, using ultraviolet lasers, and confining the interaction to the atomic scale.
The phenomenon appears to completely avoid the heat generation problem that has previously restricted the ability to make very small precise cuts.
“So far we have used the technique to demonstrate structures in diamond of size about 20 nanometres, which is the size of large molecules,” says Dr Mildren.
“However, the technique looks highly promising for doing much better, enabling manipulation of surfaces with the ultimate single atom precision, or more than a ten thousand times smaller than that possible by standard laser machining techniques.”
More information is available in the full report, published in the journal Nature.