PVC Pipes and Nanotechnology at Walla Walla
by Debbonnaire Kovacs, Jan. 21, 2015 A short article in the October, 2014 issue of The Gleaner caught my eye. “Professor Provides Glimpse into Atomic World.” That’s the sort of headline that makes you keep reading. “Tom Ekkens, Walla Walla University Physics Department chairman, has built an instrument that examines things as detailed as 7 nanometers by using a handful of basic, everyday materials,” the article said.
Really! Sounded like the kind of out-of-the-box stuff we love here at Adventist Today. I was fortunate to catch Dr. Ekkens in his office and asked him to tell me more. His ability to explain things in simple terms shows clearly that he must be a very good professor. My ability to translate what he said in this article may not be as clear!
“It says here you looked at PVC pipes at Home Depot, and said, ‘Hey, I can look at atoms with that!’” I said. “How did that work?”
“To be fair,” Ekkens said, “I’ve been building scanning tunneling microscopes since graduate school. It’s not like a whole new thing occurred to me while I was standing there by the pipes.” However, he explained, these microscopes are usually built with expensive things like sapphires, brass, and aluminum. Over the years, he has built many, and has had students build many from these expensive materials. His PVC epiphany had to do with replacing those expensive components with simple ones. If he could simplify, and get rid of the expensive machinery, it would make it possible for his students to “realize that they can build something that does extraordinary things out of common parts.”
“High quality machinery will always use stronger stuff; we’re not going to put any quality manufacturers out of business. But if we can make something simple that can see 80% of what the expensive stuff does, then that’s great.”
The PVC pipes he was looking at were patch pipes—two short pieces of pipe, one of which slides inside the other, and both of which contain O-rings. Scanning tunneling microscopes need to scan very delicately along whatever they’re looking at—in Ekkens’ class, usually graphite—so they use these patch pipes to slide their sample slowly along under the microscope.
If you electrify a small piece of wire and move it close enough to the sample for electrons to “hop across,” which is called “tunneling,” you can, by counting, tell how close you are. Dr. Ekkens said it was like reading Braille—from the bumps, the trained mind can form a picture. But in order to be close enough for electrons to do their hopping, you have to be approximately at the level of the atom.
No problem: guitar amp pickups to the rescue! Ekkens finds them on E-Bay for about a dollar apiece. An amp pickup works by detecting the vibration of the guitar string in front of it. Ekkens’ class “use them backwards—instead of picking up vibrations, we use them to make something vibrate,” thus causing the tiny movements necessary for the scanning and for the electrons to jump ship so they can be counted.
According to the Gleaner story, some of Ekkens’ other elements include hot glue, a battery pack, a tiny metal tip, a small motor with a controller, a computer with a data processing card, and two software programs he wrote.
So far, the best student-built microscope rendered a small bump that was 160 atoms wide, but Ekkens’ own microscopes are able to resolve a single atom of elemental graphite.
I asked Ekkens, “How does your love of physics and of teaching physics intersect with your faith?”
He replied, “Well, looking at atoms and so on definitely shows order in the universe, and it’s fun to see evidence of design. Trying to teach students about how complex the world is, is something that, as a Christian, I love to do.”
