AFM inventor, Calvin F Quate, dies at 95
Image: Calvin Forrest Quate (December 7, 1923 – July 6, 2019) was one of the inventors of the atomic force microscope.
Calvin F 'Cal' Quate, the Leland T Edwards Professor of Engineering, Emeritus, and a professor of applied physics at Stanford, died at his home in Menlo Park, California, on July 6. He was 95.
Quate, an electrical engineer by training, invented advanced microscopes that transformed science.
His scanning acoustic microscope, announced in 1978, used high-frequency sound waves to apply gentle pressure to objects under observation.
The acoustic microscope was as sensitive as light-based microscopes, yet delicate enough to measure the internal structures, density, elasticity and viscosity of living cells without harm.
In the mid-1980s, Quate and collaborators from IBM introduced the atomic force microscope, which transformed the burgeoning nanotechnology industry with its ability to detect previously imperceptible surface details in solid materials.
Using a nanoscale probe to apply constant pressure to solid surfaces, the atomic force microscope was able to deliver 3D images that were 1,000 times more detailed than the best optical microscopes of the time, all while retaining gentleness of his acoustic microscope.
Bob Byer, a professor of photon science and a long-time colleague from the Department of Applied Physics, remembers Quate’s hand-drawn schematic and notes for the atomic force microscope lingering on a blackboard at Stanford’s Ginzton Hall in the months preceding the invention.
He also remembers the day Quate rushed into his office, shouting: “It works!”
Quate was a highly regarded scientist who was bestowed with numerous professional accolades, including the National Medal of Science, the Kavli Prize, the Rank Prize for Opto-Electronics and the Medal of Honor from the IEEE, as well as election to the National Academy of Engineering in 1970, the National Academy of Sciences in 1975 and Britain’s Royal Society in 1995.
That same year, the editors of R&D Magazine named Quate their “Scientist of the Year,” citing him as “the genius behind acoustic and atomic force microscopy and the inspiration for a $100 million instrument industry.”
Around the Stanford campus, Quate was known as an affable and soft-spoken expert who would offer opinions only when asked and, even then, in the gentlest of manners.
“Cal was a special man,” Byer recalled. “He earned respect with very few words. Everyone listened to what Cal Quate had to say.”