September 17, 2009
AMHERST, Mass. – David S. Hall, associate professor of physics at Amherst College, has received a three-year, $469,086 grant from the National Science Foundation (NSF). The award will support Hall’s studies of gases cooled to a billionth of a degree above absolute zero—the lowest possible temperature in the universe—and will allow him to build on work done by legendary physicists Satyendra Nath Bose and Albert Einstein in the 1920s.
The NSF funding will enable Hall and his team of undergraduate researchers to delve deeper into the properties of Bose-Einstein condensates, which were first predicted theoretically by (and named after) the influential scientists. A Bose-Einstein condensate (BEC) is the peculiar and intriguing phenomenon that occurs when a gas of noninteracting particles is made extremely cold: a substantial portion of the gas populates the lowest-energy state of the system, in which the atoms behave less like individual particles and more like collective waves.
For many years, because of the limited technology and resources at their disposal, experimental physicists could only realize BECs in superfluid helium, using a system that was difficult to understand theoretically. Since 1995, however, scientists have been able to create BECs from dilute, weakly-interacting gases, thereby approaching the relative theoretical simplicity imagined by Bose and Einstein.
Hall’s NSF grant will allow him and his student assistants to continue their research on BECs, investigating the effects of interatomic interactions on the BECs, the interactions between two or more different BECs and the peculiar manifestations of superfluidity in rotating BECs. “This work is definitely on the leading edge of the kind of research being done at liberal arts colleges,” said the professor. “What we learn from it may one day contribute to a better understanding of this unusual state of ultracold matter.” He added that he hoped the work would also lead to practical applications of BECs in the future.
To create BECs in his Amherst lab and conduct his research, he and his students built their own atom refrigerator and first produced BECs in 2002. This equipment is the first of its kind at an undergraduate institution.
“I’ve been fortunate in having fantastic students collaborate with me on this project and in having access to superior facilities and staff that help make the considerable technical difficulties surmountable,” said Hall. “There are few places that routinely make these kinds of opportunities available to undergraduates.”
A 1991 Amherst graduate, Hall received A.M. and Ph.D. degrees from Harvard University and did his postdoctoral work at the University of Colorado with Eric Cornell and Carl Wieman, themselves recipients of the 2001 Nobel Prize in physics for their work on Bose-Einstein condensation. Hall joined the Amherst faculty in 1999.
Hall’s project is titled “Experiments with Bose-Einstein Condensates.” To read more, go to www.nsf.gov/awardsearch/showAward.do?AwardNumber=0855475.