Calvin F. Quate, inventor of advanced microscopes, dies at 95

The inventor of acoustic and atomic force microscopes that revealed living cells in unprecedented detail and former chair of both Applied Physics and Electrical Engineering died July 6.

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.

Calvin Quate, 1923-2019 (Image credit: L.A. Cicero)

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 akin to a phonograph needle 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.”

Respected leader

Calvin Forrest Quate was born Dec. 7, 1923, in Baker, Nevada. There, Quate learned to ride horses and tend sheep among sagebrush and pine trees. In 1934, his family relocated to Salt Lake City, Utah. Quate earned his bachelor’s degree in electrical engineering from the University of Utah in 1944 during the later days of World War II. Upon graduation, he was plucked just prior to joining General Electric to work at the top-secret Oak Ridge National Laboratory in Tennessee as part of the Manhattan Project.

After the war, Quate entered the doctoral program at Stanford where he earned his PhD in 1950. He then joined the technical research staff at Bell Telephone Laboratories to work in microwaves, eventually rising to become associate director of electronics research. In 1959, he accepted a position at Sandia Corporation and, in 1960, was appointed vice president and director of research for the company.

Quate next joined the faculty of Stanford University in 1961 as professor of applied physics and of electrical engineering. There, he would remain for the rest of his career. Quate served as chairman of the Department of Applied Physics in two separate periods, 1969-72 and 1978-81. From 1972 to 1974, he served as associate dean in the School of Humanities and Sciences. And, he chaired the Department of Electrical Engineering from 1986 to 1988. His appointment, in 1985, as the Edwards Professor was the first chair funded by the Engineering Venture Fund.

“His approach to the work he did in these positions was vintage Cal – deep thoughts and few words,” said Jim Gibbons, former dean of the School of Engineering. “His position on most matters of academic administration can be stated in two short sentences: ‘Do we need to do this?’ or ‘I’ll do it.’ I felt honored to know him and I will miss him greatly.”

Quate is survived by his wife of 23 years, Arnice Pearl Streit, a former associate dean for finance in Stanford’s School of Humanities and Sciences; daughters Robin Rain of San Mateo, California; Rozwin Liera of Mount Vernon, Washington; Holly Quate of Napa, California; and Rhoda Quate of San Diego, California; as well as Arnice’s three children from a previous marriage: Chris Guerrini of Florence, Italy; Carol Bauer of San Jose, California; and Richard Streit of Sacramento, California. Quate also had three grandchildren and three great-grandchildren. He was predeceased by his first wife, Dorothy (Marshall) Quate, in 2017.

Memorial donations can be made to Stanford’s Department of Applied Physics or Department of Electrical Engineering in the name of Calvin F. Quate.

The family has planned a private remembrance. A Stanford memorial service is being planned. Details will be announced when available.