PHYSICS DEPARTMENT

Despite a nationwide decrease in the number of students studying physics, our own numbers remain healthy and, in fact, have been growing. There are 13 incoming senior majors (’03) and 20 incoming junior majors (’04). The astrophysics route through the major, administered jointly with the Astronomy department, has been particularly popular of late. To supplement the upper level courses offered by the Astronomy department we will be adding courses on Gravity and on Elementary Particle Physics which we think will be of particular interest to Astrophysics majors. As has always been the case, Astrophysics students can choose to do their honors work in either physics or astronomy.

Pulitzer Prize winning author Richard Rhodes at Adams Memorial Theatre

In January, the Pulitzer Prize winning author Richard Rhodes visited and gave an interesting, and surprisingly optimistic talk entitled “In the Shadow of the Bomb: Nuclear Weapons Yesterday, Today and Tomorrow.” The talk was well attended by the college community. This visit was organized by Prof. Aalberts as part of his Winter Study course on The Making of the Atomic Bomb.

Last year, the college undertook a major strategic planning exercise in order to identify curricular goals for the next five to ten years. Two of the areas that were identified are of particular interest to the Physics Department: interdisciplinary teaching and tutorials.

For the last several years, we have been experimenting with courses that cross traditional disciplinary boundaries such as Protecting Information: Applications of Abstract Algebra and Quantum Physics, Materials Science: The Chemistry and Physics of Materials and Science and Religious Experience. In 2003-04 we will be offering Bioinformatics and Biological Physics. We are hopeful that as the college expands the faculty to support new curricular initiatives we will get the resources we need to teach these kinds of courses on a regular basis.

The Physics Department has been an early and enthusiastic supporter of tutorials. We have evolved a variation on the canonical tutorial format which works well for physics. The weekly cycle starts Thursday evening when students read a chapter in the text (sometimes along with an article from the literature). Friday there is a one hour lecture/discussion session for the whole class. Students then spend a few days working on problem sets. Tuesday or Wednesday each pair of students meets with the professor for an hour presenting their solutions thus far and discussing any questions that have arisen. Thursday students turn in written solutions and the whole cycle begins again. While this is a demanding schedule for students (and faculty!), we find that the extra effort is well rewarded by the improvement in student’s problem solving skills. We have converted our standard upper level courses onElectromagnetic Theory, Classical Mechanics and Applications of Quantum Mechanics into tutorials. We also offer an occasional tutorial-like reading course in Solid State Physics and will be adding one onElementary Particle Physics. Most of our graduate school bound students take at least two tutorials. The Williams tutorial program was featured in the February 15 issue of the Chronicle of Higher Education. Included in the article, “Me and My Professor,” is description of our physics tutorials and a photograph of Dave Ticehurst ’03 and Jeff Garland ’03 discussing their solution to an E&M problem with Prof. Kevin Jones.

The college has received an extraordinarily generous bequest for the support of teaching and research in the Physics Department. Mrs. Frances McElfresh Perry has left the college some 12 million dollars in honor of her father, Prof. William Edward McElfresh, who taught at Williams 1902-1936. Prof. McElfresh was chair of the Physics Department from 1905 until his retirement. This is one of the largest gifts the college has ever received. A portion of the gift will be used to create an endowed faculty chair to be named in honor of Prof. McElfresh. The college is in the early stages of determining how to best use the rest of the gift to support teaching and research in Physics. One clear priority is support for summer research students. The college has agreed to use a portion of the McElfresh/Perry gift to establish a dozen new summer student positions. When combined with the existing Somers and Synnott funds, we will be able to support not only incoming seniors but a good number of younger students as well.

Charlie Doret '02 looks over the atomic beam apparatus
he used for his thesis research with Prof. Majumder.

Finally, we are proud that one of our graduating seniors, S. Charles Doret, was selected to give an invited talk at a special session on undergraduate research at the meeting of the American Physical Society Division of Atomic, Molecular and Optical Physics held in Williamsburg, VA in May 2002. Charlie’s talk, “Precise Measurement of the Stark Shift in the Thallium 6P_1/2 → 7S_1/2 378 nm Transition,” described his thesis work with Prof. Tiku Majumder. This talk was superbly delivered and very well attended, eliciting many very positive comments from senior physicists.

Assistant Professor Daniel Aalberts taught PHYS 141, Particles and Waves---Enriched, PHYS 014, The Making of the Atomic Bomb, PHYS/MATH 210, Mathematical Methods for Scientists, and PHYS 302, Statistical Physics. In PHYS 141, he instituted bi-weekly conferences, in PHYS 014, he organized a visit by Pulitzer prize winning author, Richard Rhodes, and staged a reading of Copenhagen by Michael Frayn. He received a course development grant to substantially revise PHYS 302, creating a series of new statistical physics laboratory exercises.

Aalberts’ research included investigating the primary reaction in vision with thesis student Fritz Stabenau ’02 and studying sequence dependent kinetics of single-stranded DNA with thesis student John Parman ’02. Aalberts, Parman, and Stabenau all presented work at the American Physical Society March Meeting in Indianapolis. In the summer of 2001, Aalberts also supervised Kristina Weyer ’03 (DNA beacons) and Mike Baiocchi ’03 (Numerical Simulations in Statistical Physics). In the summer of 2002, Jeff Garland ’03 and Nathan Hodas ’03 will begin thesis projects on predicting how DNA folds.

On the Committee for Educational Policy, Aalberts led the sub-group defining and implementing the College’s new Quantitative/Formal Reasoning Requirement. He advises the Society of Physics Students and he performed at the Elizabethans’ Christmas concert, singing bass with the student/faculty quartet, With and Without.

In the fall, Associate Professor Sarah Bolton taught Physics 131,Particles and Waves, as well as Physics 109, Sound Light and Perception. In the spring, she had the great pleasure of introducing the strange world of quantum mechanics and relativity to beginning students, as she taught Physics 142, Physics Today.

During 2001-2002, Bolton worked with Alex Glenday ’02 in studies of semiconductors using an ultrafast Titanium Sapphire laser. The laser produces pulses of less than 20 femtoseconds in duration (20 x 10^-15 seconds) – short enough to take “snapshots” of electron motions and molecular vibrations. They are using the laser to determine how these very fast motions are altered when the electrons in a material are confined to two dimensions. Work on this project will continue in the summer of 2002 with Alex Glenday ’02 and Sarah Nichols ’03. Bolton has just received a National Science Foundation grant of $150,000 to support this research, and she recently completed an invited review chapter entitled High-order Coulomb Correlations in Semiconductors that summarizes the state of knowledge in the field.

The Bolton group is also starting a new collaboration with the group of Peter Parsans at Rensselaer Polytechnic Institute. The Parsans group will provide Bolton with novel “quantum dot” nanostructures, which she and her students will study using ultrafast spectroscopy.

Stuart Crampton has recently received a $10,000 award from the Center for Theology and the Natural Sciences (CTNS), a member of the Graduate Theological Union in Berkeley, CA. The award was for the design of his new course entitled Science and Religious Experience, which he taught for the first time this past spring. Although Crampton will formally retire from the faculty at the end of June 2002, he expects to continue studying, doing some teaching and perhaps also doing some writing in the field of the relationship of science to religion. He will continue to serve on the Board of Directors of Research Corporation and as a consultant to the Sherman Fairchild Foundation Scientific Equipment Program.

Crampton’s formal retirement was marked by a small ceremony at the June graduation exercises. President Shapiro noted Crampton’s enormous influence in establishing the culture of research-active faculty in the sciences at Williams.

We have enjoyed having Prof. Marek Demianski in residence for the past year, although on this visit he is teaching only in the Astronomy department. It was delightful to hear his masterful presentation of the present understanding of cosmology in his October Sigma Xi lectures “Discovering the Universe.”

Professor, and department chair, Kevin Jones continues to collaborate with the Laser Cooling and Trapping group at the National Institute of Standards and Technology in Gaithersburg, MD headed by Dr. William Phillips. In collaboration with NIST scientist Dr. Paul Lett, Jones uses the cold atom facilities at NIST to study collisions between atoms at <1/1000 degree above absolute zero. Atoms colliding in the presence of laser light can “photoassociate” to form molecules. From detailed study of these photoassociation spectra one can learn about the nature of the atomic collisions. The detailed understanding of the collision properties they have derived from these photoassociation experiments is proving to be essential background information for understanding other experiments on Bose-Einstein condensates and on proposed experiments on quantum computation.

Jones published a paper describing an experiment combining laser cooling of atoms with picosecond (10^-12 second) lasers. When a collection of cold atoms is exposed to a pulse of laser light, some of the excited atoms will collide and “associatively ionize” to produce molecular ions. Jones and colleagues showed that when the sample is exposed to two laser pulses a few nanoseconds apart, one gets a much enhanced ionization signal quite difficult to understand from an atomic collision point of view. They provided a convincing explanation of the dynamics based on a molecular picture.

The current focus of Jones’ research is to complete the spectroscopy of highest vibrational levels in the ground electronic states in Na₂. Sarah Iams ’04 joined the research group in summer 2001 and worked an experiment to test the calibration accuracy of some earlier measurements. In summer 2002, Rachel Gealy ’04 is working on a continuation of this spectroscopy experiment as well as a new, unrelated effort to look at a (possible) new source of correlated photon pairs.

In addition to his main work on photoassociation at milliKelvin temperatures, Jones was a part of a group at NIST that did a photoassociation experiment in a sample of Bose condensed atoms, a factor of 1,000,000 lower in temperature. They were able to show that it is possible to photoassociate a large fraction of this highly quantum mechanical system in a time much shorter than one would estimate from the atomic speed and spacing.

On the teaching side, Jones has been teaching our upper level tutorials on electromagnetism and classical mechanics and is endeavoring to develop polished course materials that can be passed along to future instructors. He has also been revising some of the lab exercises in our sophomore level Waves and Optics course.

During the summer of 2001, Associate Professor Protik (Tiku) Majumder supervised two students in the summer research program. Charlie Doret ’02 spent his second summer in the lab, beginning his own thesis project in earnest. Charlie continued the work begun by his predecessors, Paul Friedberg ’01, and Andrew Speck ’00, using a new thallium atomic beam apparatus and an ultraviolet laser system to measure the “Stark Shift” of thallium atoms in the presence of very large electric fields. First year student, Elliot Morrison ’04, also joined the lab and helped out with some development work for a new spectroscopy experiment to test time reversal symmetry in thallium. They bade farewell to postdoctoral associate, Dr. David Richardson, in July. Happily for David, as of June 2002, he has accepted a faculty position in the physics department at Northwest Missouri St. University.

Prof. Majumder enjoyed a very productive sabbatical leave year during 2001-2002, in which he worked in his lab at Williams with Charlie, submitted and was awarded a new $230,200 NSF grant, and made a number of brief research trips, giving seven invited presentations on his research at small colleges, research universities, and conferences. The 3-year NSF grant, beginning July 2002, will be used to purchase new equipment, support students, and hire a new postdoctoral research associate. In May 2002, Charlie and Prof. Majumder attended the APS Division of Atomic, Molecular, and Optical Physics annual meeting where Charlie gave the invited talk mentioned above.

The Majumder group continues to pursue high-precision diode laser spectroscopy of thallium in their atomic physics lab. A better understanding of the structure of this complex atom is essential to be able to interpret recent precision measurements of parity nonconservation in thallium in terms of fundamental physics. During his extended tenure in the lab, Charlie has worked on all aspects of the latest atomic beam experiment, taking complete ownership of this project. This year Charlie worked on production, stabilization, and tuning of the UV laser system. He also completed final development and testing of the atomic thallium beam apparatus and the vacuum system. Finally, he was able to develop the necessary data acquisition infrastructure, and to collect and thoroughly analyze substantial amounts of high-precision Stark Shift data. His written thesis reflects the breadth and depth of his contributions to this work, and includes an analysis of the data and presentation of results sufficiently complete to serve as the basis for a manuscript on the subject, presently being written, and slated for submission to the journal Physical Review in June (with Paul Friedberg ’01, Andrew Speck ’02, and David Richardson as co-authors.)

The department has nominated Charlie for the national Apker Award, given annually by the American Physical Society for the best undergraduate thesis research project. We are happy to have Charlie remaining in the lab for part of summer 2002, prior to beginning a physics Ph.D. program at Harvard University this fall. Majumder looks forward to having incoming thesis student, Christopher Holmes ’03, as well as Joe Kerchkoff ’05, and Josh Cooperman ’05, join the lab in June.

Associate Professor Jefferson Strait taught PHYS 201, Electricity and Magnetism, in the fall term and PHYS 132, Electromagnetism and the Physics of Matter, in the spring term. During Winter Study period, he taught the holography course, which is now in its fourteenth year. Strait also finished his term as a member of the Executive Board of the New England Section of the American Physical Society, attending the section meeting at Keene State College.

Strait and his students have built an optical fiber laser designed to produce pulses of light about 10^-12 seconds long. Unlike most lasers, which use mirrors to confine light to the laser cavity, an optical fiber laser uses a loop of fiber as its cavity. A section of fiber doped with erbium serves as the gain medium. Strait and his students pump the gain medium with 1.06 µm, conveniently the same wavelength at which optical fiber is most transparent and therefore most suitable for telecommunications. During the summer and fall of 2001, John Spivack ’02 worked in Strait’s lab with the fiber laser. During the summer of 2002, Davy Stevenson ’04 will continue this work. The eventual goal is to study how these short pulses propagate in optical fiber.

Professor William Wootters was on leave for the academic year 2001-2002. He used the sabbatical to continue his research in quantum information theory - the theory of information embodied in microscopic objects such as individual electrons - as well as to visit other physicists who are working on similar problems. In October, he traveled to Oxford University where he served as the external examiner of a D. Phil. student, and later in the fall he spent a month at the Institute for Theoretical Physics in Santa Barbara, participating in their program entitled “Quantum Information: Entanglement, Decoherence and Chaos.” In the spring semester, he visited physicists at Carnegie Mellon University and MIT, and spent a week at the University of Bristol in the UK where there is a strong interdisciplinary group working on quantum information. He also participated as an invited speaker at a conference on Quantum Entanglement in San Feliu de Guixols, Spain. (Entanglement is a remarkable kind of correlation that many regard as the most characteristic feature of quantum mechanics). Finally, he attended symposia honoring two physicists who were reaching different milestones: in Princeton, New Jersey, there was a symposium in honor of ninety-year-old John A. Wheeler, who was Wootters’ postdoctoral advisor; and at Cornell University, David Mermin, who in the latter part of his career has contributed significantly to the foundations of quantum mechanics and quantum information theory, was honored with a symposium on the occasion of his retirement.

In the summer of 2002, Wootters will be doing research with two students, Naila Baloch ’03 and Kate Gibbons ’03, who both plan to pursue thesis projects.

During the summer of 2001, Dwight Whitaker arrived on campus from Eric Cornell’s Bose-Einstein condensation research group in Boulder, Colorado and began setting up his lab to produce Bose-Einstein condensates of rubidium-87 with the help of two summer students, Wei-Li Deng ’03 and Leon Webster ’04. During the academic year, Dwight taught Introductory Quantum Mechanics in the fall semester and The Physics of Everyday Life in the spring semester. October brought the happy news that Whitaker’s post-doctoral mentors, Eric Cornell and Carl Wieman, had shared in the 2001 Nobel Prize in Physics.

Staff Physicist and Coordinator of Science Facilities, Bryce Babcock, collaborated with Professor Jay Pasachoff on observations of the total solar eclipse in Lusaka, Zambia in June 2001. He was a co-author with Pasachoff, Kevin Russell ’00 and Dan Seaton ’01 of a paper published inSolar Physics, analyzing data from the 1999 eclipse in Romania. Preparations are in progress for experiments at the December 2002 eclipse in Ceduna, Australia. He is also participating with Prof. Pasachoff and Steve Souza in observing the occultation of two stars by Pluto, predicted for July 20 and August 20, to study the planet’s atmosphere. This work is in collaboration with several other teams in a program headed by Dr. James L. Elliot of MIT. (For further details regarding these experiments and publications see the Astronomy Departmental and Faculty Publications sections of this report.)

In addition to his work developing research and instructional laboratory apparatus for the sciences, Babcock taught an independent study course on introductory robotics in the spring semester. He is working with Science Administrative assistant Kate Fletcher and a team of students from Information Technology’s WIT summer 2002 program to develop a new web-based directory of sciences at Williams. He continues to edit of the Report ofScience at Williams, the annual review of science activities at Williams, which is provided in both print and web-accessible versions. In addition to these college activities, he welcomed the completion of construction on new facilities for the Williamstown Community Bible Church in the summer of 2001, for which he had acted as “clerk of the works,” and assumed the new title of grandfather with the birth of his first grandchild, Grace Lyn, on July 1, 2002.

Bethany E. Cobb	David M. Glick
Rossen L. Djagalov	Nathan O. Hodas
S. Charles Doret	Christopher D. Holmes
Caleb I. Fassett	Sarah R. Nichols
David (Mike) Gioiello	Sarah J. Reynolds
Alexander G. Glenday	Hans F. Stabenau

[Colloquia are held jointly with Astronomy. See Astronomy section for additional listings.]

Dr. Julia Steinberger, M.I.T. – Cambridge, MA, Class of 1960 Scholars Program

“Trapping and Probing Ultracold Hydrogenic Atoms”
Dr. Charles Conover, Colby College, Class of 1960 Scholars Program

“Coherent Control of Quantum Systems”
Dr. Humphrey Maris, Brown University, Class of 1960 Scholars Program

“The Fission of the Electron”
Richard Rhodes, Pulitzer Prize Winner, Class of 1960 Scholars Program

“In the Shadow of the Bomb: Nuclear Weapons Yesterday, Today and Tomorrow”
Dr. Michael Zuker, Rensselaer Polytechnic Institute, Class of 1960 Scholars Program

“Algorithms and Statistics for Nucleic Acid Secondary Structure Prediction”
Julie Rapoport ’97, Northwestern University, Class of 1960 Scholars Program

“Engineering After Williams”
Noel Goddard, Rockefeller University, Class of 1960 Scholars Program

“Sequence Dependent Dynamics of Single Stranded DNA”
Jamie Williams, N.I.S.T. – Gaithersburg, MD, Class of 1960 Scholars Program

“Spin Waves in an Ultracold Dilute Gas of Atoms”

Professor Daniel Aalberts

“Intramolecular Competition and the First Step in Vision”

Simon’s Rock College of Bard

“Mechanically Tuning the Color of Polyacetylene”

American Physical Society March Meeting
Professor Sarah Bolton

“Low Dimensional Chaos in a Femtosecond Ti:Sapphire Laser” (with Mark Acton ’00)
Gordon Conference on Nonlinear Optics, Colby Sawyer college, New Hampshire, August 2001

“Ultrafast Spectroscopy of Nanostructures – Windows into Many-Body Interactions”
Rensselaer Polytechnic Institute – Condensed Matter and Optics colloquium, October 2001
S. Charles Doret ’02

“Precise Measurement of the Stark Shift in the Thallium 6P_1/2 → 7S_1/2 378 nm Transition”

American Physical Society Division of Atomic, Molecular and Optical Physics, Williamsburg, VA

May 29 – June 1, 2002 (invited talk at a special session on Undergraduate Research)
Professor Kevin Jones

“The Hot and Cold Show”
Williamstown Elementary School, Third Grade Science Night, April 11, 2002

“Making Cold Sodium Molecules”
Les Houches Workshop on Cold Molecules, March 4 – 8, 2002 (presented by P.D. Lett) P.D. Lett, K. Jones, and others

“Two-Color Photoassociation Spectroscopy of the Triplet Ground State of Na₂”
American Physical Society Division of Atomic Molecular and Optical Physics. May 29 – June 1, 2002 – Williamsburg, VA (presented by L. de Araujo) L. de Araujo, K. Jones, and others
Professor Protik (Tiku) Majumder

“Diode Lasers, Thallium Atoms, and Tests of Fundamental Physics”

Mt. Holyoke College (invited department colloquium), October 11, 2001

“Precise Atomic Structure Measurements in Thallium and Tests of Fundamental Physics:

York University, Toronto, CA (invited department colloquium), October 30, 2001

“Precise Atomic Structure Measurements in Thallium and Tests of Fundamental Symmetries”

Institute for Theoretical Atomic and Molecular Physics, Harvard/Smithsonian,
Workshop: “Tests of Fundamental Symmetries in Atoms and Molecules” (invited talk), December 1, 2001

“Diode Lasers, Thallium Atoms, and Tests of Fundamental Physics”

Colby College (invited department colloquium), February 21, 2002

“Precise Atomic Structure Measurements in Thallium and Tests of Fundamental Physics”

University of California, Berkeley (invited AMO seminar), March 5, 2002

“Diode Lasers, Thallium Atoms, and Tests of Fundamental Physics”

Middlebury College (invited department colloquium), April 3, 2002

“Atomic Structure Measurements and Fundamental Symmetry Tests in a Thallium Atomic Beam”

APS Division of Atomic, Molecular, and Optical Physics Meeting - College of William and Mary (contributed), May 30, 2002
Professor William Wootters

“Quantifying Entanglement”

Institute for Theoretical Physics, Santa Barbara, CA – November 2001

“Parallel Transport in an Entangled Ring”

Workshop on Quantum Information, Institute for Theoretical Physics, Santa Barbara, CA – December 2001

“Quantum Entanglement as a Resource for Communication”

Carnegie-Mellon University – Physics Department Colloquium – February 2002

Colgate University – Physics Department Colloquium – April 2002

“Sharing Entanglement”

MIT – Quantum Information Seminar – March 2002

Workshop on Quantum Entanglement, San Feliu de Guixols, Spain – March 2002

University of Bristol, UK – Theoretical Physics Seminar – May 2002
Professor Dwight Whitaker

“Construction and Coherent Control of Cold Atom Clouds”

Amherst College – November 15, 2001

Professor Daniel Aalberts

“Information Networks in Cells”
Summer Research Program

“Photoexcitation of Conducting Polymers: Ultrafast Photoisomerization”
Bronfman Tuesday Lunch Group
Professor Jefferson Strait

“Photonic Bandgap Materials”
Physics Summer Research series – July 26, 2001
Professor William Wootters

“Random Quantum States”
Physics Department Summer Seminar – June 2001

S. Charles Doret	Ph.D. program in Physics at Harvard University
Alexander G. Glenday	Ph.D. program in Physics at Harvard University
John M. Parman	Ph.D. program in Economics at Northwestern University
Sarah J. Reynolds	Teaching middle school science
Daniel W. Schwab	Unknown
John H. Spivack	Ph.D. program in electrical engineering at Pennsylvania State University
Hans F. Stabenau	Ph.D. program in Physics at University of Pennsylvania

Daniel T. Bissex	Pursuing career in music
Gabriel B. Brammer	Employment at Space Telescope – Baltimore, MD
Shoshana C. Clark	Teaching in Honduras
Bethany E. Cobb	Ph.D. program in Astronomy at Yale University
Rossen L. Djagalov	Received Horace Clark fellowship to study Comparative Literature in Moscow
Caleb I. Fassett	Unknown
David (Mike) Gioiello III	Unknown
David M. Glick	Unknown