Atomic Force Microscope Sensitivity More Sensitive Thanks to Laser

Aug 16, 2014 09:11 AM EDT | Matt Mercuro

Australian National University researchers have discovered a way to make microscope probes 20 times more sensitive and able to identify forces as tiny as weight of a virus.

The technique involves laser beams to cool a nanowire probe ti minus 265 degrees Celsius.

"The level of sensitivity achieved after cooling is accurate enough for us to sense the weight of a large virus that is 100 billion times lighter than a mosquito," said Professor Ping Koy Lam, the leader of the Quantum Optics Group, according to

The research is good news on a number of levels, as it can enhance the resolution of atomic-force microscopes.

Atomic-force microscopes are able to get a very precise measurement of the microsoping characteristic of a specimen by scanning a wire probe over the surface.

The probes are susceptible to vibration however, though with this new technique, vibrations can be stopped through cooling.

"At room temperature the probe vibrates, just because it is warm, and this can make your measurements noisy," said Dr. Ben Buchler, a co-author of the research that is published in Nature Communications, according to

"We can stop this motion by shining lasers at the probe," he said.

The lasers are able to stop the vibration, and makes the probe warp and move due to the heat. Movement can be controlled however, as scientists were able to manipulate the warping to counter the thermal vibration of the probe.

The probe can't be operated while the laser is on however. It has to be turned off first and measurement needs to be taken before the probe warms up again, according to

"We now understand this cooling effect really well," says PhD student Harry Slatyer, according to "With clever data processing we might be able to improve the sensitivity, and even eliminate the need for a cooling laser."

See Now: OnePlus 6: How Different Will It Be From OnePlus 5?

© 2021 Auto World News, All rights reserved. Do not reproduce without permission.
Get the Most Popular Autoworld Stories in a Weekly Newsletter

Join the Conversation

Real Time Analytics