The University of Connecticut 2152 Hillside Road Storrs, CT 06269-3046 DEPARTMENT OF PHYSICS NEWS Volume I Issue 8 July, 2004 Anthony Leggett, Katzenstein Distinguished Lecturer Friday, September 10, 2004 Anthony (Tony) J. Leggett, MacArthur Professor at the University of Illinois at Urbana- Champaign, delivers the Katzenstein Distinguished Lecture on September 10, 2004. The title of the lecture is “Superfluidity, Phase Coherence, and the New Bose-Condensed Alkali Gases.” We wel- come the public and encourage all science and engineering students to attend. Professor Leggett shared the 2003 Nobel Prize in Physics with Alexei A. Abrikosov and Vitaly L. Ginzburg. These physicists made groundbreaking contributions to the theory of superconductors and superfluids, low-temperature systems with the property that a current or a flow in the fluid, once set up, may continue without ever slowing. Superfluidity is widely referred to as a macroscopic quan- tum phenomenon; a bucketful of liquefied helium behaves as if it had a “macroscopic wave func- tion” obeying quantum mechanics. Professor Leggett’s Nobel Prize winning contribution thirty years ago was to introduce multicomponent wave functions to explain the experimentally observed properties of the 3He superfluid. Since the discovery of Bose-Einstein condensation in dilute atomic vapors nine years ago, superfluidity and other macroscopic quantum phenomena are now more topical than ever, and the macroscopic wave function remains the most important tool of a theorist in this field. Professor Leggett is also well known for his studies of when and how a macroscopic object can behave quantum mechanically. In fact, he might object to referring to superfluidity as a macroscopic quantum phenomenon because superfluids show neither superposition nor entanglement of macroscopic objects. Initially a classics graduate, Professor Leggett took up physics and received his doctorate at Oxford University in 1964 under the tutelage of the late Dirk ter Haar. His Nobel Prize winning work was done at University of Sussex. He has held his current position at the University of Illinois since 1983, where he continues to make important contributions to superfluidity and quantum mechanics. 1 2004 Charles A. Reynolds Distinguished Lecture in Physics Professor John Reppy, Cornell University, capacity in an unparalleled temperature range delivered the Reynolds Distinguished Lecture on about T to within a temperature difference as April 26. Prof. Reppy received a BA with em- low as 2 nanoKelvin from the lambda point. A phasis on both math and physics in 1954 at very-high-resolution calorimeter with special UConn and was then offered work in Charles thermal isolation allowed such studies to be Reynolds’ Laboratory for 75 cents per hour. made, which enabled very precise comparisons This was a turning point for him. Inspired by with the predictions of the Renormalization Reynolds’ enthusiasm and love of physics, Group, and will serve as stimulus for further Reppy chose physics and received an MA in work in this area. 1956 from UConn. At Yale he worked with C. T. Reppy introduced the idea of a supersolid in Lane, receiving his Ph.D. in 1962. From ‘62 to connection with the search for a superfluid ‘66, he was an Assistant Professor at Yale. In transition in solid helium dispersed in a porous ‘66 he joined the Physics Department at Cornell medium. The results of studies by Chan and where he is presently the John Wetherill Profes- Kim of Penn State University were recently sor of Physics. He is reported in Nature. the recipient of They grew solid 4He numerous awards inside a porous and honors, including Vycor glass disk and the Fritz London observed the reso- Memorial Award in nant period of a 1981. He is a mem- torsional pendulum, ber of the National which supported the Academy of Sci- enclosed disk con- ences. taining the solid Reppy has a helium. As the longstanding interest temperature is in fundamental reduced below 0.1 K, problems in low- they see a sudden temperature physics, Professor Emeritus Dwight Damon with Professor John drop in the period of especially the proper- Reppy before the lecture (left to right). this system, which is ties of superfluid helium, and has made many dependent on oscillation amplitude. significant contributions in this field. In his These results indicate a supersolid phase. lecture, he focused on the superfluid transition Vacancies and other defects are expected to be of liquid 4He. This “Lambda ( ) transition,” so present in solid 4He. These zero-point vacan- named because of the shape of the temperature cies and defects can, in principle, permit the dependence of the heat capacity in the vicinity appearance of superfluidity in the solid. In 1970, of the superfluid transition, occurs at 2.17K. Prof. A. J. Leggett suggested the possibility of a He reviewed the history of superfluids, supersolid, and at that time proposed experi- beginning with the observations of Kapitza, Allen ments to search for this phase. and Misener in 1938. In particular, he ad- Prof. Reppy spoke proudly of the accom- dressed the critical behavior of the heat capacity plishments of M. H. (Moses) Chan, for whom he as one approaches extremely close to T . had been the doctoral thesis advisor. The Since the temperature of the superfluid transi- creativity in important and challenging experi- tion decreases with increasing pressure, gravity- ments is a hallmark of Prof. Reppy’s laboratory induced pressure variation broadens the and continues in this new work reported by his Lambda transition. Recently, Chui and co- former student Moses Chan. A spirited discus- workers experimented in the low-temperature sion followed his talk. (Prof. A. J. Leggett has facility of the NASA space shuttle. This gravity- agreed to present the 2004 Katzenstein, as free environment allowed studies of the heat noted on our cover.) 2 The Norman Hascoe Lectures on the Frontiers of Science The Department of Physics has continued to play a leading role in a new lecture series funded by Mr. Norman Hascoe of Greenwich, Connecticut, aimed at exciting undergraduates with scientific interests in frontier areas of science. Each lecture is open to the public and is followed by a reception and an informal panel discussion. In our sixth year, we had five outstanding lectures in the general field of nanoscale sci- ence: 1. Fleming Crim, Chemistry, University of Wisconsin-Madison, “Controlling Chemical Reactions and Watching Vibrational Energy Flow in Gases and Liquids” 2. Richard Martel, INRS-Eau, Terre & Environnement, Quebec, “Scientific Issues with Carbon Nanotube Transistors” 3. Jean Dalibard, Ecole Normale Supérieure, “Atomic Bose-Einstein Condensates: Quantum Coher- ence and Superfluidity” 4. Elias Greenbaum, Oak Ridge National Laboratory, “New Vistas in Photosynthesis Research: Renewable Hydrogen Production, Algal Biosensors for Environmental Protection and Artificial Sight” 5. Herbert Walther, Physik der Universität München, “Quantum Optics of Single Atoms” Nanoscale science involves application of the concepts and techniques of physics to systems at a higher level of complexity (e.g. the supramolecular and macromolecular) and is the focus of major federal research funding initiatives. A comparably exciting lecture program for next year is being planned. Prizes and Awards Education/Physics, and one a Math major/Physics Phil Best minor. The graduates included four with high honors, three with a second degree in Math, and one The Katzenstein Prize for the best science essay with a second degree in Music. by a graduating senior was won by two students this year: “Calculations of Potential Curves for Alkali Dimers at Excited Asymptotes X(ngs)+X*(nes)” was submitted by Brad Normand, who is advised by The University of Connecticut Excellence in High William Stwalley, and “Application of the Weyl- School Physics Teaching Award went to David Titchmarsh-Kodaira Spectral Theorem to Soluble Scrofari, from Staples High School in Westport. Models of Molecular Ionization” was entered by Currently the President of the Connecticut Associa- Chris Gauthier, advised by Gerald Dunne. It’s the tion of Physics Teachers, David’s accomplishments first time that the committee has declared a tie. Brad can perhaps best be seen through the achievements of plans to get his Ph.D. in physics at UConn and his students. He is advisor to Staples High School continue his studies in music as well. Chris has NEDC (National Engineering and Design Competi- entered the graduate program at the University of tion) team, national first place winner, Spring 2001. Michigan for his physics degree. In 2002 one of David’s students was a member of the U.S. Physics Team. Another of his students, mentored at Yale, won the Intel and Siemens- Inductees into Sigma Pi Sigma, the physics honor Westinghouse student research award. society, were undergraduates Kurt Doughty, Aaron Fagan, Melissa Grakowsky, Caroline Loglisci, Kandra Painter, Anthony Palladino, Chris Regini and Calvin Zulick, and graduate student James Andrey Dobrynin was awarded the 2003-04 O’Brien. The Special Colloquium was presented by Directors Award for Faculty Excellence by the Professor Reinhold Blumel, of Wesleyan University. Polymer Program in the Institute of Materials Sci- The title of his talk was “Charged-Particle Confine- ence. The award is to recognize Andrey’s excellence ment with Walls of Pure Energy.” Professor Blumel and leadership in teaching, research and service to the gave a delightful presentation, punctuated with program. His selection was based on his contribu- demonstrations on ion trapping. All of the published tions as well as a nomination by the faculty of the research he described had been carried out by under- program. Andrey’s name will be entered on a perma- graduate students. nent plaque of awardees displayed outside the Poly- A total of 10 students graduated in Physics this mer Program office, and he will receive $1000. past year, plus one in Engineering Physics, one in Congratulations and keep up the good work, Andrey! 3 Studying Scattering Professor Munir Islam just spent his sabbatic leave (Spring 2004) at the State University of New York at Stony Brook.