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PRODID:UW-Madison-Physics-Events
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UID:UW-Physics-Event-2187
DTSTART:20111014T203000Z
DURATION:PT1H0M0S
DTSTAMP:20260420T132219Z
LAST-MODIFIED:20110524T162434Z
LOCATION:2241 Chamberlin Hall (coffee at 4:30 pm)
SUMMARY:Quantum Phase Transitions and Scale Invariance of Atomic Quant
 um Gases\, Physics Department Colloquium\, Cheng Chin\, University of 
 Chicago
DESCRIPTION:Atoms at ultralow temperatures are fascinating quantum obj
 ects\, which can tunnel through barriers\, repel or attract each other
 \, and interfere like electromagnetic waves. This wavy behavior of ult
 racold atoms evidently illustrates the particle-wave duality as discus
 sed in quantum physics. By loading repulsively interacting atoms into 
 tiny optical cells (or optical lattices)\, we show that the wavy natur
 e of the atoms can be completely suppressed. At the same time\, the ga
 seous sample develops an interesting multi-layer structure with densit
 y plateaus\, resembling a multi-tier wedding cake. Our observation of 
 the cake structure in 2D ultracold gases [1] raises new prospects to i
 nvestigate the dynamics and transport across the phase boundary [2] an
 d to identify universal scaling laws in the (quantum) critical regime 
 [3]. Surprising findings along these directions will be presented and 
 discussed.<br>
\n<br>
\nReferences:<br>
\n[1] In situ Observation of i
 ncompressible Mott-insulating domains in atomic gases Nathan Gemelke\,
  Xibo Zhang\, Chen-Lung Hung\, Cheng Chin Nature 460\, 995 (2009) <br>
 
\n[2] Slow Mass Transport and Statistical Evolution of An Atomic Gas 
 Across the Superfluid-Mott Insulator Transition Chen-Lung Hung\, Xibo 
 Zhang\, Nathan Gemelke\, Cheng Chin Phys. Rev. Lett. 104.160403 (2010)
 <br>
\n[3] Observation of scale invariance and universality in two-dim
 ensional Bose gases Chen-Lung Hung\, Xibo Zhang\, Nathan Gemelke\, Che
 ng Chin Nature (2011) doi:10.1038/nature09722
URL:https://www.physics.wisc.edu/events/?id=2187
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