John J. Quinn

John J. Quinn, a world-renowned theoretical physicist and former Willis Lincoln Chair of Excellence and Distinguished Professor at the University of Tennessee, Knoxville, died on 8 October 2018 after a short illness. He is survived by his wife of 60 years, Betsy V. Quinn, by their four children, Daniel Quinn, Elizabeth Quinn-Stine, Heather Quinn-Bader, and Jennifer Quinn (with whom he was very happy to have co-authored a paper), by nine grandchildren, three great grandchildren, and many former students, postdocs, colleagues, and friends.

Quinn was born in Brooklyn, New York, on 25 September 1933. He attended schools in Brooklyn, Queens, and Tarrytown and graduated with a BS in 1954 from St. John’s University in Queens. He was a PhD student of Richard Ferrell’s at the University of Maryland, College Park, and received his degree in 1958. He spent an additional year at Maryland as a postdoc. He subsequently accepted a position at RCA Laboratories in Princeton, New Jersey, and was a member of technical staff there until 1964. In 1961 he was the Mary Amanda Wood Visiting Lecturer at the University of Pennsylvania, and he also spent a year as visiting professor at Purdue University in 1964, where he established close professional and personal relationships that he maintained for many years.

In 1965, at the age of 31, he became a full professor in the Department of Physics at Brown University, where he remained for the next 24 years. While at Brown, he was visiting professor at SUNY Stony Brook in 1969, at the University of Rome (fall/winter 1971–72) and the Max Planck Institut für Kohlenforschung (spring/summer 1972), at the University of California, Irvine in 1977, and at the University of Maryland, College Park in 1988. He held the prestigious Ford Foundation Professorship at Brown University from 1985 through 1988 and also held a joint appointment as Professor of Engineering in 1988–89.

Quinn served as Associate Provost at Brown University in 1984–85 and as dean of the faculty from 1986–89. During this period, he was a faculty representative in a gender-discrimination class action suit against Brown University. Characteristically, he was very fair and reasonable and was of value to both the women and the university. His interest and proficiency in administration, combined with his outstanding record of scholarly achievement, led to possible positions as president/chancellor at several institutions. He accepted the offer of the chancellorship at the University of Tennessee, Knoxville in 1989, where he was also Professor of Physics and Professor of Engineering Science and Mechanics. Characteristically, Quinn told friends that he believed that the University of Tennessee was really hiring Betsy as wife of the chancellor, and he was the trailing spouse as chancellor. In 1992 he returned to what he loved most, physics, as the Willis Lincoln Chair of Excellence. While at the University of Tennessee, he was visiting professor at the University of New South Wales and at the National Magnet Laboratory and the University of Florida in 2000.

Quinn interacted with many scientists and engineers, and he was a gifted explicator of complex theory in simple physical terms and in connecting his own work with experiment. At Brown, to expand his appreciation of experimental work, he collaborated closely with Stephen Bishop on an experimental project to probe helicon wave dispersion in metals at low temperatures. He worked directly on the experiments, even to the extent of transferring liquid helium and taking and analyzing data.

Quinn was a pioneer in the application of field theoretic methods to many-body theory of condensed-matter systems, and he made important contributions to the fields of magneto-transport in metals and semiconductors, and to the understanding of many-body effects in artificially structured, low-dimensional electronic materials. His contributions to many-body theory date from his early work on the “self-energy approach” to interactions in a degenerate electron gas, which emphasized the properties of quasiparticles, the energy dependence of their lifetime, and their “effective” Fermi liquid interactions; aspects of this work were of critical importance in understanding electron spectroscopies. In addition, Quinn and Sergio Rodriguez did the first comprehensive study of the wave vector and frequency-dependent quantum mechanical response of an electron gas in a dc magnetic field. He and his coworkers later included the effect of electron collisions and applied their results to study acoustic attenuation; they made the first evaluation of helicon–phonon coupling, the first explanation of direct electromagnetic generation of sound, and the proposal of acoustic NMR. His groups were also the first to calculate the effect of electron–electron interactions on single-particle energies, and on collective excitations and other many body effects in layered electron gas systems.

More recently, Quinn focused on one of the most challenging problems in condensed matter physics: fractional quantum Hall systems, and the explanation of when and why the composite fermion (CF) picture is valid. He and collaborators developed a CF hierarchy scheme based on reapplying the CF transformation to quasiparticles in partially filled CF shells and also elucidated the nature of the excitonic complexes and their contributions to photoluminescence. His final paper, with two co-authors from the mathematics department at Tennessee (published posthumously), was on “Strong fermion interactions in fractional quantum Hall states.”

During his academic career, Quinn mentored 17 PhD students and six postdoctoral scholars, several of whom have gone on to outstanding careers of their own. In 1974–75, he and Phillip J. Stiles organized the first international conference on the electronic properties of two-dimensional Systems (EP2DS), held at Brown University in 1975. The latest in what became an important series of biennial conferences, EP2DS-22 was held at Pennsylvania State University in 2017. Quinn also served the physics community significantly as a member of the Solid State Sciences Committee of the National Research Council. He chaired the Panel on Artificially Structured Materials and produced a report by the same name (National Academy Press, Washington, DC, 1985).

Quinn had a lifelong interest in sports, and for many years he was an avid (and good) golfer. While he was chancellor, he and Betsy became good friends with Pat Summit, the legendary coach of women’s basketball at the University of Tennessee.

John J. Quinn was an outstanding theoretical physicist, an excellent academic administrator, and a wonderful human being. He will be sorely missed by family and his many friends, former students, postdoctoral scholars, and colleagues.