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Observation of a Persistent Non-Equilibrium State in an Extremely Isotropic Harmonic Potential

Event Details

Event Dates: 

Tuesday, May 26, 2015 - 4:00pm

Seminar Location: 

  • JILA X317

Speaker Name(s): 

Dan Lobser

Speaker Affiliation(s): 

JILA (Cornell group)
Seminar Type/Subject

Scientific Seminar Type: 

  • JILA Thesis Defense

Event Details & Abstract: 

Ludwig Boltzmann made tremendously important contributions to the problem of connecting macroscopic, empirical phenomena with microscopic, atomistic dynamics. Boltzmann was confronted with various strong objections to his work. For example, Boltzmann's atomistic explanations presuppose the reality of atoms, a notion that was vigorously rejected in some circles. Then too, there was the critique that Boltzmann's /H/-theorem, put forth as a microscopic explanation for the Second Law of Thermodynamics, could hardly account for irreversible physics when the individual two-atom collisions were each reversible. Still intriguing today is the existence of special cases of the Boltzmann equation in which time-varying distributions of atoms resist the imperative of equilibration, even in the presence of collisions. Such improbable systems of atoms have only very recently been realized experimentally [1,2]. Perhaps one of the more interesting cases is the vanishing damping of the monopole breathe-mode oscillation in a spherically symmetric harmonic oscillator. Until now, this phenomenon has been experimentally inaccessible due to the difficulty in generating isotropic harmonic confinement. This thesis discusses a new magnetic trap capable of producing spherical confinement and presents the first experimental realization of this historically significant oddity using a magnetically trapped gas of 87Rb atoms.

 

[1]  Toshiya Kinoshita, Trevor Wenger, and David S. Weiss. A quantum newton’s cradle. /Nature/, *440*(7086):900–903, 04 2006.

[2]  F. Chevy, V. Bretin, P. Rosenbusch, K. Madison, and J. Dalibard. Transverse Breathing Mode of an Elongated Bose-Einstein Condensate./Physical Review Letters/, *88*(25):250402, June 2002