by Leslie Virostek

 On a wintry day this past March, Steve Lundeen ‘69 [below] came back to Trinity. A professor at Colorado State University and a researcher in the field of atomic, molecular, and optical physics, Lundeen had been invited by Professor of Physics Mark P. Silverman, a grad school chum, to give a lecture to physics students and faculty members at their weekly seminar series.

            Much to his delight, Lundeen found Trinity’s physics community to be in many ways unchanged: The department was still small and friendly. Its students still studied together and thrived on the individual attention of faculty members. “It was a good major,” he recalls. The big difference between then and now, Lundeen notes, is really in the area of facilities and equipment. “When I was at Trinity there was one computer on the campus,” he recalls. “You had to program it with paper tape!” He adds with a chuckle, “There’s been quite a bit of change in the computing environment.”

            Something is very different about Steve Lundeen, too. He is a Fellow of the American Physical Society, the professional organization for physicists that boasts some 42,000 members, publishes the world’s most prestigious physics research journals, and through major conferences and meetings promotes communication and collaboration among researchers. Membership in the APS is de rigueur for any serious physicist; everybody who is anybody belongs. The organization’s Fellows, who are nominated by their peers, represent the cream of the crop. Accordingly, each year’s batch of Fellows makes up no more than one half of one percent of the membership. Being recognized as a Fellow is kind of like being inducted into the physics hall of fame, only unlike athletic halls of fame, selection occurs not at the end of an illustrious career, but at the height of it, when one has achieved a sort of critical mass of contributions to the field.

     This is the story of not one, but three Trinity physics graduates who have achieved the distinction of APS Fellow. Lundeen, Michael Stavola ‘75 [left], and Arthur Champagne ‘78 [below] each became members of the APS as graduate students or shortly thereafter. As university faculty members and researchers, they each earned the respect of peers. And each was designated a Fellow almost exactly 20 years after the Trinity physics department awarded their bachelor’s degrees. The common trajectory of these physics all-stars is interesting to say the least and perhaps even mathematically improbable. How does a school like Trinity, which graduates a small handful of physics majors each year, have such a strong showing among the APS’s elite? It might be a phenomenon worth studying.

 

Lundeen’s “excited” states

          Lundeen earned his Ph.D. at Harvard in 1975. He taught at Harvard for eight years and then at the University of Notre Dame for the next 10 years before heading to Colorado State in 1993. In his research over the past 20 years, Lundeen has been exploring a special class of atoms and molecules, those in high-energy “excited” states. Lundeen’s work has focused on high-angular momentum states, called Rydberg states, in which one excited electron is bound to the atom or molecule in a characteristically more circular orbit. Says Lundeen, “Because of the fact that the electron is in a more circular orbit, its interactions with the rest of the atom or molecule are very different than in the more familiar states.” Lundeen has found that by studying atoms and molecules in their Rydberg states we can learn things about them that can’t be learned any other way. And in fact Lundeen has been able to actually measure properties of ions that theorists have been unable to calculate and model. This approach, he notes, might be applied in the future to research on such elements as uranium and thorium. “We think we can learn things about those very heavy ions that are very difficult to calculate and conceivably could be useful to people who are interested in modeling their chemistry,” he says. “That could have relevance, in the very long-term, to nuclear waste disposal, for example.”

 

Stavola’s defects and impurities

           Roughly 500 researchers worldwide study the properties of defects and impurities in semiconductors, the materials from which all modern electronics are made. Michael Stavola, a professor at Lehigh University since 1989, is well known among this cadre of scientists. The author or coauthor of 130 technical papers, Stavola has also chaired or cochaired the two most important professional conferences in the field. His contributions include introducing innovative methods to bring to light critical information about the structures and electronic properties of defects. Stavola says, “I use the absorption of light--spectroscopy--to study the atomic-scale properties of impurities.” Stavola, who worked for nine years at Bell Laboratories after earning his Ph.D. at the University of Rochester, explains that impurities are added to semiconductors to enhance their electrical and optical properties. Understanding the nature of defects and impurities is thus critical to engineering better computer chips and electronic devices.

            Stavola’s career focus on the intersection of physics and engineering is rooted in his Trinity education. A double major in physics and engineering, Stavola says, “I had outstanding teachers in both departments.” On the engineering side there were people like August E. Sapaga, Karl Hallden Professor of Engineering, Emeritus. “Sapaga taught a course in materials science that started my interest in the properties of materials,” says Stavola. “The faculty in physics got me interested in understanding things at a more fundamental level.”

            Stavola says that a course on statistical mechanics, taught by Professor of Physics Harvey S. Picker, was “the best course I have had, ever.” He also singles out Picker as “the person who has had the greatest impact on my career.” Throughout graduate school, Stavola relied upon Picker’s guidance and support, and they’ve been good friends ever since. Says Stavola, “Now, 30 years since I first met Harvey, I see him at least once a year and still call him for advice.”

 

Champagne’s reactions

       Physicists know that fundamentally comprehending the very smallest processes ultimately promotes understanding of larger-scale phenomena. This may be particularly true for the research area of nuclear astrophysics, where learning about the nuclear reactions of atoms informs our understanding of the workings of the universe. Art Champagne, Eduoard Morot-Sir Professor of Nuclear Physics at the University of North Carolina, uses such tools as giant accelerator facilities (with their 200-meter-long underground tubes) to measure the same types of nuclear reactions that occur in stars. Such research, he notes, is very basic. Elements are created within the high-heat, high-density stellar environment, so his work sheds light on how elements are made. “We also can learn about stars that way,” he says, “because astronomers can go and look at stars and measure elemental abundances and compare with what we’ve measured in the laboratory, and we can work out the details of how the star evolved and how it’s constructed. The problem is that stars last for a very long time, so that the reactions occur over billions of years, and we have to try to measure them in the lab in a matter of months.” The solution? “We have to do what we can and use what we know about nuclear physics to fill in the blanks.”

            Nuclear astrophysics answers questions about what will happen to the sun and to all the stars in the long term and how old the galaxy is, notes Champagne. More compelling, perhaps, is that the work affects one’s point of view. “You can see where you sit with respect to the rest of the universe, which I think is interesting if you can realize it,” says Champagne. “It gives you some perspective on your role in the grand scheme.”

            Champagne’s first love was always astronomy, he says, although he was interested in all of the sciences when he entered Trinity. His challenge, particularly with physics, was that his math background was not so strong. Champagne says, “I had to work really hard at it. The faculty was incredibly supportive and it was a fantastic environment to be in. I really was able to excel because of the atmosphere and because of the support.” An example of that support--and the individual attention physics majors receive--is how Picker devised an independent study that combined the quantum mechanics and mathematical methods that would cement his student’s grasp on the two interrelated areas. “It was great,” says Champagne. “In fact, I’m publishing a paper this summer that made me go back to some of those notes.”

            Champagne’s most lasting connection to Trinity may be through Jarvis Professor of Physics Albert J. Howard, Jr. Champagne had taken an advanced lab course with Howard and then worked in his nuclear physics lab at Trinity. He continued collaborating with Howard through graduate school at Yale (where Howard continues to base much of his research) and beyond. “Actually we worked together right up until two years ago,” says Champagne. “We were trying to measure something that ultimately turned out to be unmeasurable, but it was a great experience.” From early on in his education, he notes, “I got to be a partner in a real research project that was ongoing.”

            Can the special dynamics of Trinity’s rigorous but nurturing physics department help explain the achievements of Champagne and his fellow APS Fellows from Trinity? Don’t ask the physics faculty members. They are loath to toot their own horns. And don’t ask the Fellows, either. They are scientists after all, and theorizing without adequate research and evidence is anathema to them. But Champagne admits to being surprised by Trinity’s representation among the Fellows and thinks the department and its dedicated faculty deserve some credit: “I think they owe themselves a pat on the back.”

            Lundeen remarks, “Being a Fellow to me represents recognition that I am a part of a research community, and that has been very rewarding. Normally you might think of science as an individual thing, but it’s really not that way at all. It’s very much a community thing. And I remember my days at Trinity with the other physics majors as the beginning of that kind of community.”