Austen Lamacraft
Department of Physics, University of Virginia
Collective phenomena in ultracold atomic gases
Research
By definition, all motion should come to a stop at absolute zero. Within billionths of a degree of that extreme temperature - or rather, lack of temperature - - the atoms and molecules in a gas, normally zipping around and bouncing off one another at near supersonic speeds, come to nearly a complete halt.
Nearly.
But as Cottrell Scholar Austen Lamacraft points out, "Heisenberg's uncertainty principle tells us that absolute localization is impossible, and that the positions of even supercold atoms have quantum fluctuations."
Mostly these fluctuations don't amount to much. But Lamacraft adds that for very light atoms, or the electrons that are free to move inside a metal atom, for example, these quantum effects "are so strong that the particles never freeze." The result is something called Bose-Einstein condensation, a very weird form of matter that defies all of our normal expectations.
In the exciting world of supercold physics, Lamacraft is using his Cottrell Scholar Award money to study the interplay of Bose-Einstein condensation - also called "superfluidity" -- and magnetism, specifically in "bosonic" gases.
The world is divided in the fermions and bosons. The definitions of these two types of subatomic particles are complicated and confusing, and they sometimes overlap. But in the most simplistic of terms, fermions are usually tied to matter, and bosons are usually associated with forces - although fermions can also display bosonic behavior, as in superconductivity. (It gets a lot more confusing from there.)
Using numerical simulation, Lamacraft hopes to understand the nature and mechanism of magnetic ordering - how bosons arrange themselves magnetically in ultracold gases.
"This is pure research on the very edge of our human understanding of the forces of nature. There is no telling where such work might one day lead," says Silvia Ronco, program officer for Research Corporation for Science Advancement (RCSA), sponsor of the Cottrell Scholar Awards.
Education
Lamacraft will also use his Cottrell Scholar Award to develop a problem-based, laboratory-style class encouraging physics majors hone their mathematical skills in an interactive and collaborative setting. "Having identified the transition from lower division mathematics to upper division physics as a weak point in the preparation of our majors," he says, "the goal of the new class is to simultaneously develop mathematical ‘dexterity' and to find out how physicists conceptualize and use the mathematics they've have already learned."
FOLLOW
US ON: