Profile: The small world of Dr. Robert Cohn

Dr. Robert CohnFor almost three decades, Dr. Robert Cohn has remained a fixture at the University in the Department of Electrical and Computer Engineering. While there, Cohn has focused his research on nanofabrication, soft matter, nano-manipulation optics, laser material processing, to name a few fields of study. For Cohn, it started off not with a direct interest in engineering, but a study of literature.

“In 1975, I finished my undergraduate degree in English. I was really interested in music at the time, and I got a job with a traveling band named the Blue Things. I ran the sound. The one thing that the Blue Things had, they had some albums, they were a contemporary after the Beatles came through. They had somewhat of a national reputation. They would go into small towns to perform,” says Cohn.

After a while, Cohn felt that he needed something more stable, and settled down to continue his education in Kansas City at the University of Kansas.

“I wanted to be a sound engineer, so I joined the electrical engineering project. In 2 ½ years, I got my engineering degree. My main goal was to finish up at the end of my time there, and take a course on acoustics,” says Cohn.

It was during that time that he wrote a term paper on surface acoustic wave filters and ultrasonic filter, detected by launching acoustic waves across a Piezo crystal. The data detected was then intended for use in radio functions. It was through that research that Cohn came into contact with Texas Instruments in their radar division, which served as a parallel to his work with acoustics, where he worked after his master’s.

Returning for his PhD, Cohn refocused his efforts on becoming a primary investigator, and began developing research on optical devices, which led to nano-scale fabrication.

A member of the Department of Electrical and Computer Engineering since 1989, Cohn’s tenure at the University has seen an expansion of those pursuits to into soft matter, a broad term relating to liquids to gels, polymeric liquids, a study relative to how semi-solid fluids will react in different environments.

He explains, “if you take a rubber band and you stretch it and heat it, it actually contracts. You can make engines out of that material, by getting an accentuated motion.”

Cohn adds, “Cells are made up of all kinds of compartments and little motors moving matter around. When you start to look at these things, you start to find how stiff the protein filament is. You start to look at the physics of that. You come up with these common numbers, how much force is required to do that. The numbers are around pico-newton, it sounds really small, but on the other hand, there are zillions of those motors in your muscles. There little pico-Newton’s working together to create force.”