Transport and phase coherence studies of a quantum gas in a disordered potential
Hitchock, James Michael
Hulet, Randall G.
Master of Science
The Study of transport and phase coherence in a Bose-Einstein condensate (BEC) of 7 Li subjected to a 1D disordered potential, provides an excellent system to explore the effects of impurities on a quantum gas. Observations of the median cloud position as the BEC is moved through the disorder potential provide evidence of inhibited transport due to classical reflections. Careful study of the damping coefficient for dipole oscillations shows a power law relationship with disorder strength ( V D ). A highly elongated BEC and large disorder length scale, (σ d = 14 pm), allow direct probing of disorder induced density modulations in the in-situ BEC. Large density fluctuations are observed to evolve from the in-situ density modulations for moderate V D , and phase coherence is suppressed at large V D . An improved speckle pattern has been designed, for future experiments, with a reduced σ d and an aspect ratio that more closely matches the BEC.
Atoms & subatomic particles; Pure sciences