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Title: Discrete Symmetries and 1/3-Quantum Vortices in Condensates of F=2 Cold Atoms

Abstract

In this Letter we study discrete symmetries of mean field manifolds of condensates of F=2 cold atoms, and various unconventional quantum vortices. Discrete quaternion symmetries result in two species of spin defects that can only appear in integer vortices while cyclic symmetries are found to result in a phase shift of 2{pi}/3 (or 4{pi}/3) and therefore 1/3- (or 2/3-) quantum vortices in condensates. We also briefly discuss 1/3-quantum vortices in condensates of trimers.

Authors:
;  [1]
  1. Department of Physics and Astronomy, University of British Columbia, Vancouver, B.C., V6T 1Z1 (Canada)
Publication Date:
OSTI Identifier:
20957712
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 10; Other Information: DOI: 10.1103/PhysRevLett.98.100401; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CONDENSATES; MEAN-FIELD THEORY; PHASE SHIFT; QUANTUM MECHANICS; SPIN; SYMMETRY

Citation Formats

Semenoff, Gordon W., and Zhou, Fei. Discrete Symmetries and 1/3-Quantum Vortices in Condensates of F=2 Cold Atoms. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.100401.
Semenoff, Gordon W., & Zhou, Fei. Discrete Symmetries and 1/3-Quantum Vortices in Condensates of F=2 Cold Atoms. United States. doi:10.1103/PHYSREVLETT.98.100401.
Semenoff, Gordon W., and Zhou, Fei. Fri . "Discrete Symmetries and 1/3-Quantum Vortices in Condensates of F=2 Cold Atoms". United States. doi:10.1103/PHYSREVLETT.98.100401.
@article{osti_20957712,
title = {Discrete Symmetries and 1/3-Quantum Vortices in Condensates of F=2 Cold Atoms},
author = {Semenoff, Gordon W. and Zhou, Fei},
abstractNote = {In this Letter we study discrete symmetries of mean field manifolds of condensates of F=2 cold atoms, and various unconventional quantum vortices. Discrete quaternion symmetries result in two species of spin defects that can only appear in integer vortices while cyclic symmetries are found to result in a phase shift of 2{pi}/3 (or 4{pi}/3) and therefore 1/3- (or 2/3-) quantum vortices in condensates. We also briefly discuss 1/3-quantum vortices in condensates of trimers.},
doi = {10.1103/PHYSREVLETT.98.100401},
journal = {Physical Review Letters},
number = 10,
volume = 98,
place = {United States},
year = {Fri Mar 09 00:00:00 EST 2007},
month = {Fri Mar 09 00:00:00 EST 2007}
}
  • A new method is applied to measure the wavelength-resolved quantum yields of I(/sup 2/P/sub 1/2/) for six molecules relevant to the iodine I(/sup 2/P/sub 1/2/) atoms and accounts for the strong exciplex emission, also at 1.3 ..mu..m, from the I(/sup 2/P/sub 1/2/)--iodide molecules. In addition, digital processing is used to correct for noise, quenching, and the detector rise time. These features avoided the shortcomings of previous measurements. The following molecules were investigated: CF/sub 3/I, C/sub 2/F/sub 5/I, i-C/sub 3/F/sub 7/I, n-C/sub 3/F/sub 7/I, n-C/sub 6/F/sub 13/I, and 1,2-C/sub 2/F/sub 4/I/sub 2/. All six iodides present high yields of I(/sup 2/P/submore » 1/2/) at the pumping wavelengths of 308 and 248 nm used. The high I(/sup 2/P/sub 1/2/) yields for the molecules n-C/sub 6/F/sub 13/I and 1,2-C/sub 2/F/sub 4/I/sub 2/ are reported for the first time.« less
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  • The reaction of Re{sub 2}O{sub 7} with XeF{sub 6} in anhydrous HF provides a convenient route to high-purity ReO{sub 2}F{sub 3}. The fluoride acceptor and Lewis base properties of ReO{sub 2}F{sub 3} have been investigated leading to the formation of [M][ReO{sub 2}F{sub 4}] [M = Li, Na, Cs, N(CH{sub 3}){sub 4}], [K][Re{sub 2}O{sub 4}F{sub 7}], [K][Re{sub 2}O{sub 4}F{sub 7}]{center_dot}2ReO{sub 2}F{sub 3}, [Cs][Re{sub 3}O{sub 6}F{sub 10}], and ReO{sub 2}F{sub 3}(CH{sub 3}CN). The ReO{sub 2}F{sub 4}{sup {minus}}, Re{sub 2}O{sub 4}F{sub 7}{sup {minus}}, and Re{sub 3}O{sub 6}F{sub 10{sup {minus}} anions and the ReO{sub 2}F{sub 3}(CH{sub 3}CN) adduct have been characterized in the solidmore » state by Raman spectroscopy, and the structures [Li][ReO{sub 2}F{sub 4}], [K][Re{sub 2}O{sub 4}F{sub 7}], [K][Re{sub 2}O{sub 4}F{sub 7}]{center_dot}2ReO{sub 2}F{approximately}3}, [Cs][Re{sub 3}O{sub 6}F{sub 10}], and ReO{sub 3}F(CH{sub 3}CN){sub 2}{center_dot}CH{sub 3}CN have been determined by X-ray crystallography. The structure of ReO{sub 2}F{sub 4}{sup {minus}} consists of a cis-dioxo arrangement of Re-O double bonds in which the Re-F bonds trans to the oxygen atoms are significantly lengthened as a result of the trans influence of the oxygens. The Re{sub 2}O{sub 4}F{sub 7}{sup {minus}} and Re{sub 3}O{sub 6}F{sub 10}{sup {minus}} anions and polymeric ReO{sub 2}F{sub 3} are open chains containing fluorine-bridged ReO{sub 2}F{sub 4} units in which each pair of Re-O bonds are cis to each other and the fluorine bridges are trans to oxygens. The trans influence of the oxygens is manifested by elongated terminal Re-F bonds trans to Re-O bonds as in ReO{sub 2}F{sub 4}{sup {minus}} and by the occurrence of both fluorine bridges trans to Re-O bonds. Fluorine-19 NMR spectra show that ReO{sub 2}F{sub 4}{sup {minus}}, Re{sub 2}O{sub 4}F{sub 7}{sup {minus}}, and ReO{sub 2}F{sub 3}(CH{sub 3}CN) have cis-dioxo arrangements in CH{sub 3}CN solution. Density functional theory calculations at the local and nonlocal levels confirm that the cis-dioxo isomers of ReO{sub 2}F{sub 4}{sup {minus}} and ReO{sub 2}F{sub 3}(CH{sub 3}CN), where CH{sub 3}CN is bonded trans to an oxygen, are the energy-minimized structures. The adduct ReO{sub 3}F(CH{sub 3}CN){sub 2}{center_dot}CH{sub 3}CN was obtained by hydrolysis of ReO{sub 2}F{sub 3}(CH{sub 3}CN), and was shown by X-ray crystallography to have a facial arrangement of oxygen atoms on rhenium.« less
  • A nonadiabatic theory of photoassociation spectra and spontaneous emission processes in diatomic molecules is presented. This theory was applied in nearly exact nonadiabatic calculations of the photoassociation intensities to the A {sup 1}{sigma}{sub u}{sup +}(1 {sup 1}S+1 {sup 1}D), c {sup 3}{pi}{sub u}(1 {sup 3}P+1 {sup 1}S), and a {sup 3}{sigma}{sub u}{sup +}(1 {sup 3}P+1 {sup 1}S) manifold of states for two colliding calcium atoms at ultralow temperatures and of the spontaneous emission coefficients to the ground X {sup 1}{sigma}{sub g}{sup +} electronic state. The calculations were based on most recent state-of-the-art ab initio results for the potential energy curvesmore » for the ground X {sup 1}{sigma}{sub g}{sup +} and excited A {sup 1}{sigma}{sub u}{sup +}(1 {sup 1}S+1 {sup 1}D), c {sup 3}{pi}{sub u}(1 {sup 3}P+1 {sup 1}S), and a {sup 3}{sigma}{sub u}{sup +}(1 {sup 3}P+1 {sup 1}S) states, for the spin-orbit and nonadiabatic coupling matrix elements, and for the transition dipole moment governing the A {sup 1}{sigma}{sub u}{sup +}<-X {sup 1}{sigma}{sub g}{sup +} transitions. The computed photoassociation spectrum shows several transitions in the detuning frequency range up to -3000 GHz. This frequency range corresponds to vibrational levels of the J{sup '}=1 state of Ca{sub 2} that can mostly be assigned to the c {sup 3}{pi}{sub u} state. The two by far most intense lines at a detuning frequency around -800 GHz correspond to the last two bound rovibrational levels lying below the 1 {sup 3}P+1 {sup 1}S asymptote which are heavily mixed and can partly be assigned to the A {sup 1}{sigma}{sub u}{sup +} state. The corresponding lifetimes and Franck-Condon factors suggest that these levels can be detected experimentally and should show a relatively efficient spontaneous emission to the ground state. An analysis of the branching ratios describing the probability of the decay from these two levels to bound vibrational levels of the ground electronic state shows that the decay will end in the levels with the vibrational quantum number between 10 and 16 with a total probability well over 90%.« less
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