Location via proxy:   [ UP ]  
[Report a bug]   [Manage cookies]                
  • Rapid Communication

Broad universal Feshbach resonances in the chaotic spectrum of dysprosium atoms

T. Maier, I. Ferrier-Barbut, H. Kadau, M. Schmitt, M. Wenzel, C. Wink, T. Pfau, K. Jachymski, and P. S. Julienne
Phys. Rev. A 92, 060702(R) – Published 14 December 2015
PDFHTMLExport Citation
Abstract
Authors
Article Text
  • ACKNOWLEDGMENTS
    • Supplemental Material
    References

    Abstract

    We report on the observation of weakly bound dimers of bosonic dysprosium with a strong universal s-wave halo character, associated with broad magnetic Feshbach resonances. These states surprisingly decouple from the chaotic background of narrow resonances, persisting across many such narrow resonances. In addition they show the highest reported magnetic moment μ≃20μB of any ultracold molecule. We analyze our findings using a coupled-channel theory taking into account the short range van der Waals interaction and a correction due to the strong dipole moment of dysprosium. We are able to extract the scattering length as a function of magnetic field associated with these resonances and obtain a background scattering length abg=91(16)a0. These results offer prospects of a tunability of the interactions in dysprosium, which we illustrate by observing the saturation of three-body losses.

    • Figure
    • Figure
    • Figure
    • Received 5 June 2015

    DOI:https://doi.org/10.1103/PhysRevA.92.060702

    ©2015 American Physical Society

    Authors & Affiliations

    T. Maier1, I. Ferrier-Barbut1,*, H. Kadau1, M. Schmitt1, M. Wenzel1, C. Wink1, T. Pfau1, K. Jachymski2, and P. S. Julienne3

    • 15. Physikalisches Institut and Center for Integrated Quantum Science and Technology, Universität Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart, Germany
    • 2Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
    • 3Joint Quantum Institute, University of Maryland and National Institute of Standards and Technology, College Park, Maryland 20742, USA

    • *Corresponding author: i.ferrier-barbut@physik.uni-stuttgart.de

    Article Text (Subscription Required)

    Click to Expand

    Supplemental Material (Subscription Required)

    Click to Expand

    References (Subscription Required)

    Click to Expand
    Issue

    Vol. 92, Iss. 6 — December 2015

    Reuse & Permissions
    Access Options
    Author publication services for translation and copyediting assistance advertisement

    Authorization Required

    Log In
    Other Options
    ×

    Images

    • Figure 1
      Figure 1

      Atom-loss spectroscopy at a temperature of 2.4μK mapping the Feshbach spectrum of Dy164 in J=8,mJ=−8 with 100mG resolution. The atom number is normalized to a reference number Nref taken at low field every 30 images.

      Reuse & Permissions
    • Figure 2
      Figure 2

      Broad Feshbach resonances of Dy164. (a) Atom-loss spectroscopy at T=500nK with a resolution of 20mG. This spectrum shows one broad feature overlapping with many narrow resonances. (b) Binding energy of weakly bound dimers measured by magnetic field modulation spectroscopy (red circles). The solid (dashed) lines are obtained by fits of our data to the coupled-channel calculations (universal expression); from these fits we extract abgΔ (Table 1). (c) The red circles are obtained by converting the Eb(B) data using the coupled-channel calculations for a(Eb). The sold lines are a fit to this data using Eq. (1). The dashed lines are the scattering length resulting from the fit of Eb(B) by the universal expression assuming abg=91a0 (see main text).

      Reuse & Permissions
    • Figure 3
      Figure 3

      Atom loss spectroscopy for different experimental starting conditions and wait times. Final atom number N normalized to the initial one N0 as a function of magnetic field, with a resolution of 100mG. Green: initial temperature, T0=2.4μK; initial density: n0=6.1(2.0)×1012cm−3, wait time t=2s; blue: T0=0.5μK,n0=3.7(1.3)×1012cm−3,t=500ms; red: T0=0.3μK,n0=4.6(1.6)×1012cm−3t=300ms. The temperature dependence of the saturation is well reproduced by the model of universal loss dynamics of unitary Bose gases of Ref. [28] (solid horizontal lines). The shaded regions represent the uncertainty on the results of the model given a one-standard deviation on all experimental parameters entering the model (temperature, atom number, trap frequency, and depth).

      Reuse & Permissions
    ×

    Sign up to receive regular email alerts from Physical Review A

    Log In

    Cancel
    ×

    Search

    Article Lookup

    Paste a citation or DOI
    Enter a citation
    ×