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Superfluidity near localization: supersolid and superglass
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- Author / Creator
- Dang, Long
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The main theme of this thesis is the interplay between superfluidity and localization,
in a system of strongly correlated Bose particles. Driving this investigation is the search
for yet unobserved phases of matter, such as the so-called supersolid. Using state-of-the-
art, numerically exact computer simulations, we have carried out an extensive theoretical
investigation of the effects of long-range interactions, inhomogeneity, disorder and frustration in a simple model of lattice Bosons. In particular, we explore the scenario of
vacancy- and interstitial-based supersolid phases of hard core bosons on a square lattice,
interacting repulsively via a nearest-neighbour and next-nearest neighbour potential. Secondly, in an attempt to model the physics of a layer of helium adsorbed on a corrugated
substrate, an additional superlattice of the absorption sites is imposed to the system of
hard core bosons, and the resulting low temperature phase diagram is studied. Finally,
the possibility of actually inducing by disorder superfluidity (superglass) in a system that
does not display it in the absence of disorder is demonstrated. The quantitative and qual-
itative predictions at which we have arrived appear to be at least in principle testable
experimentally, for example by performing measurements on ultracold atoms in optical
lattices. -
- Subjects / Keywords
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- Graduation date
- Fall 2010
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- Type of Item
- Thesis
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- Degree
- Doctor of Philosophy
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- License
- This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.