Inventors reveal road to atomic force microscopy
Image: This year, researchers used AFM to measure van der Waals forces between individual atoms for the first time. [University of Basel].
Inventors of the atomic force microscope and winners of this year's Kavli Prize in Nanoscience, Gerd Binnig, Christoph Gerber and Calvin Quate, tell their story in an interview published online this week.
Binnig and Gerber discuss their inspiration for the device, how they solved problems through sport, and why their invention continues to propel science at the nanoscale.
As Gerber, now professor of physics at the Swiss Nanoscience Institute, University of Basel, says in the interview: "We came up with a very precise way to measure forces with a cantilever, and within just two or three years, someone figured out how to use a laser to get even better resolution,".
It took only five years until the first commercial instrument, and from there, there was no holding it back," he adds. "AFM has turned into the most powerful and most versatile toolkit that we have for doing nanoscience. And it keeps evolving."
"In just the past few years, researchers have learned to pick up a molecule on the tip of an AFM, which we can think of as the needle on a record player, and reveal chemical bonds while imaging molecules on surfaces," he highlights. "Nobody thought that ever would be possible."
Using a form of atomic force microscopy, researchers can differentiate the chemical bonds in a single molecule of nanographene. [IBM)]
Unlike optical microscopes, AFM doesn't use light to illuminate an object. Instead, it measures the tiny forces between a sharp tip at the end of a cantilever and the surface of an object.
As it scans a surface, what emerges is an image so clear that researchers can even distinguish chemical bonds within a molecule. They can also use the tip to create and cleave those bonds, and push atoms around.
"[AFM] lets us look at the molecules that make life possible... and see things we could not see before," explains Binnig, who received the Nobel Prize in 1986 for the scanning tunneling microscope, AFM's predecessor.
"It teaches us how to make changes to surfaces or molecules that we attempted blindly in the past," he says. "And it has been used in so many different scientific studies, from looking at polymers and chemical reactions to modifying surfaces at the atomic level."
Read the interview here.