College of Liberal Arts and Sciences at Iowa State University

Personal milestones

Fellowship is nice, but physics' Michael Tringides prefers excitement of discovery.
Michael Tringides has joined a very exclusive group.

But Tringides, professor of physics and astronomy and Ames Laboratory senior physicist, is more excited about the discoveries he and his research group have made in recent years than his election as a Fellow of the American Physical Society (APS).

"It (APS Fellow) means something for sure," he said. "But it's the work that you perform that makes the difference to me. You know what is important in your work and which work is a milestone."

At least two milestones have occurred for Tringides in recent years. First, and foremost, is the discovery his group made in finding unusual growth mode at low temperature. Contrary to conventional expectations, the group found that uniform height metal islands can be grown on Silicon substrates. The discovery has led to novel ways to control growth of uniform atomic-scale structures.

The work done by Tringides and his research group (associate scientist Myron Hupalo and graduate students Vincent Yeh and Michael Yakes) is basic research within the U.S. Department of Energy's Ames Laboratory to learn more about the microscopic processes that control the growth of custom-made materials.

It is essential for atomic structures and ultrathin metal films to be grown in uniform sizes and with highly ordered genometries for technological applications that can include switches, lasing materials and semiconductors. Such atomic structures will allow computer chips to run faster.

The work of the group may prove critical in the further miniaturization of silicon-based electronic devices, a major undertaking in light of the silicon industry's huge role in technological innovation and production.

"It's essential that these structures are grown in a robust and reproducible way, with easy size selection," he said.

Tringides originally published his group’s findings in 2000. Because of the surprising and interiguing results, Tringides attempted to interest other groups in the research.
He thought he had a group from Taiwan excited about the project.

"But we didn't hear from them for a long time," he recalled. "Then there was this earthquake in Taiwan. I thought maybe their lab was destroyed and they wouldn't be able to work on the project."

Soon after the earthquake, Tringides received an e-mail from the group.

"That was really thrilling for me," he said. "Not only did they look at similar work, but they fully confirmed our unexpected discovery.

" Having someone confirm your novel discovery - now that's a thrill. The impact of the work will last forever, even if the research is reviewed 100 to 200 years from now."

Tringides estimates six groups are now working on the issue worldwide as a result of their pioneering discovery.

But it is not the only milestone in Tringides' research career.

Just last year his group published research on the "devil's staircase" phase diagram. This is one of the outstanding theoretical predictions in statistical physics and its realization in nature has been a great challenge to experimentalists. This discovery is one of the best case examples of a "devil's staircase" ever found.

"Hopefully others will begin to do experiments along the same lines," Tringides said.

Ironically, Tringides was honored by the APS not for these recent discoveries, but mainly for his earlier work on surface diffusion. He was honored for "his pioneering contributions in the elucidation of equilibrium and non-equilibrium adatom diffusion on single crystal surfaces."

Tringides was one of two Iowa State physicists named an APS Fellow, an honor granted to no more than one-half of one percent of the current membership of the Society. The election by their peers of Tringides and John Hill, professor of physics and astronomy, brings the number of APS Fellows in the Department of Physics and Astronomy to 13.