Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:cond-mat/0305180 · Physical Review A

Characterization of elastic scattering near a Feshbach resonance in 87Rb

Thomas Volz, Stephan Dürr, Sebastian Ernst, Andreas Marte, Gerhard Rempe

Published Jul 23, 2003• 85 citations
arXivHTMLPDF

Abstract

The s-wave scattering length for elastic collisions between ${}^{87}\mathrm{Rb}$ atoms in the state $|{f,m}_{f}〉=|1,1〉$ is measured in the vicinity of a Feshbach resonance near 1007 G. Experimentally, the scattering length is determined from the mean-field-driven expansion of a Bose-Einstein condensate in a homogeneous magnetic field. The scattering length is measured as a function of the magnetic field and agrees with the theoretical expectation. The width of the resonance is determined to be 0.20(3) G, the position of the zero crossing of the scattering length is found at 1007.60(3) G.

DOI
10.1103/physreva.68.010702

Related papers

Improved characterization of elastic scattering near a Feshbach resonance in 85Rb

Jacob Roberts, James P. Burke, N. R. Claussen +3 more

We report extensions and corrections to the measurement of the Feshbach resonance in ${}^{85}\mathrm{Rb}$ cold atom collisions reported earlier [J. L. Roberts et al., Phys. Rev. Lett. 81, 5109 (1998)]. In addition to a better determination of the position of the resonance peak [154.9(4) G] and its width [11.0(4) G], improvements in our techniques now allow the measurement of the absolute size of the elastic-scattering rate. This provides a measure of the s-wave scattering length as a function of magnetic field near the Feshbach resonance and constrains the Rb-Rb interaction potential.

arXiv:physics/0104053•Physical Review A•Jul 5, 2001•47 citations

Critical collisional opacity in a Bose-Einstein condensate

J. Schuster, Andreas Marte, S. Amtage +3 more

Summary form only given. In a Bose-Einstein condensate, due to the very low temperature, the s-wave scattering length can be used as a measure for the strength of the atom-atom interaction. Under typical experimental conditions, this interaction is weak and hence can be treated in terms of a mean field. However, when scattering length is large or the density is high, the mean field approximation breaks down. In this collisional (hydrodynamic) regime, effects of the interactions such as quantum depletion or shifts in the frequencies of the elementary excitations become large. It is therefore of great interest to study condensates close to or in the collisional regime. It has been demonstrated in recent experiments that the scattering length and thus the interactions among the atoms can be tuned by means of a Feshbach resonance (Inouye et al, 1998; Courteille et al., 1998; Vuleti et al., 1999; Cornish et al., 2000). In the vicinity of Feshbach resonances, however, the increase of the cross-section for elastic collisions is accompanied by a dramatic increase of particle losses. In this paper we report on the observation of anomalous losses from a /sup 87/Rb condensate with a high column density in the absence of an inelastic scattering resonance.

Quantum Electronics and Laser Science Conference•Nov 13, 2002•2 citations

Observation of a Feshbach Resonance in Cold Atom Scattering

Daniel J. Heinzen, Ph. W. Courteille, R. S. Freeland

Due to atomic interactions, a dilute gas Bose-Einstein condensate acquires a self- energy proportional to the two-body scattering length a. This self-energy strongly influences the stability, formation rate, size and shape, collective excitations, and other properties of a condensate. For a given atomic species at zero magnetic field, the scattering length is fixed, and this had led to a rather limited range of interaction strengths in experiments. However, it has been predicted that a magnetically tunable Feshbach resonance could be used to strongly modify scattering lengths [1]. We have observed such a Feshbach resonance in collisions of ultracold 85Rb(f =2, mf=−2) atoms in a magnetic field B. From our measured resonance position and width, we infer that the scattering length a2,−2 for collisions of these atoms has the dispersive resonance form.

•May 3, 1998•0 citations

s-wave elastic collisions between cold ground-state Rb87 atoms

Nathan R. Newbury, Christopher J. Myatt, Carl Wieman

We have measured the elastic-scattering cross section of $^{87}\mathrm{Rb}$ atoms in the \ensuremath{\Vert}F=1,${\mathit{m}}_{\mathit{F}}$=-1〉 ground state at 25 \ensuremath{\mu}K. The cross section is almost purely s wave at these temperatures and has a value of (5.4\ifmmode\pm\else\textpm\fi{}1.3)\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}12}$ ${\mathrm{cm}}^{2}$. We have searched for the predicted Feshbach-type resonances in the elastic cross section [Tiesinga et al., Phys. Rev. A 46, 1167 (1992)] as a function of magnetic field. There are no resonances with a magnetic-field width \ensuremath{\ge}2 G over a magnetic-field range of 15--540 G.

Physical Review A•Apr 1, 1995•51 citations

Strongly Enhanced Inelastic Collisions in a Bose-Einstein Condensate near Feshbach Resonances

J. Stenger, S. Inouye, Michael R. Andrews +3 more

The properties of Bose-Einstein condensed gases can be strongly altered by tuning the external magnetic field near a Feshbach resonance. Feshbach resonances affect elastic collisions and lead to the observed modification of the scattering length. However, as we report here, the observed rate of inelastic collisions was strongly enhanced in a sodium Bose-Einstein condensate when the scattering length was tuned to both larger or smaller values than the off-resonant value. These strong losses impose severe limitations for using Feshbach resonances to tune the properties of Bose-Einstein condensates.

arXiv:cond-mat/9901056•Physical Review Letters•Mar 22, 1999•406 citations

Resonant Magnetic Field Control of Elastic Scattering in Cold R 85 b

Jacob Roberts, N. R. Claussen, James P. Burke +3 more

A magnetic field-dependent Feshbach resonance has been observed in the elastic scattering collision rate between atoms in the $F\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2,M\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\ensuremath{-}2$ state of ${}^{85}\mathrm{Rb}$. Changing the magnetic field by several Gauss caused the collision rate to vary by a factor of 1${0}^{4}$, and the sign of the scattering length could be reversed. The resonance peak is at 155.2(4) G and its width is 11.6(5) G. From these results we extract much improved values for the three quantities that characterize the interaction potential: The van der Waals coefficient ${C}_{6}$, the singlet scattering length ${a}_{S}$, and the triplet scattering length ${a}_{T}$.

Physical Review Letters•Dec 7, 1998•499 citations
The s-wave scattering length for elastic collisions between 87Rb{}^{87}\mathrm{Rb}87Rb atoms in the state ∣f,mf〉=∣1,1〉|{f,m}_{f}〉=|1,1〉∣f,mf​〉=∣1,1〉 is measured in the vicinity of a Feshbach resonance near 1007 G. Experimentally, the scattering length is determined from the mean-field-driven expansion of a Bose-Einstein condensate in a homogeneous magnetic field. The scattering length is measured as a function of the magnetic field and agrees with the theoretical expectation. The width of the resonance is determined to be 0.20(3) G, the position of the zero crossing of the scattering length is found at 1007.60(3) G.
We report extensions and corrections to the measurement of the Feshbach resonance in 85Rb{}^{85}\mathrm{Rb}85Rb cold atom collisions reported earlier [J. L. Roberts et al., Phys. Rev. Lett. 81, 5109 (1998)]. In addition to a better determination of the position of the resonance peak [154.9(4) G] and its width [11.0(4) G], improvements in our techniques now allow the measurement of the absolute size of the elastic-scattering rate. This provides a measure of the s-wave scattering length as a function of magnetic field near the Feshbach resonance and constrains the Rb-Rb interaction potential.
Summary form only given. In a Bose-Einstein condensate, due to the very low temperature, the s-wave scattering length can be used as a measure for the strength of the atom-atom interaction. Under typical experimental conditions, this interaction is weak and hence can be treated in terms of a mean field. However, when scattering length is large or the density is high, the mean field approximation breaks down. In this collisional (hydrodynamic) regime, effects of the interactions such as quantum depletion or shifts in the frequencies of the elementary excitations become large. It is therefore of great interest to study condensates close to or in the collisional regime. It has been demonstrated in recent experiments that the scattering length and thus the interactions among the atoms can be tuned by means of a Feshbach resonance (Inouye et al, 1998; Courteille et al., 1998; Vuleti et al., 1999; Cornish et al., 2000). In the vicinity of Feshbach resonances, however, the increase of the cross-section for elastic collisions is accompanied by a dramatic increase of particle losses. In this paper we report on the observation of anomalous losses from a /sup 87/Rb condensate with a high column density in the absence of an inelastic scattering resonance.
Due to atomic interactions, a dilute gas Bose-Einstein condensate acquires a self- energy proportional to the two-body scattering length a. This self-energy strongly influences the stability, formation rate, size and shape, collective excitations, and other properties of a condensate. For a given atomic species at zero magnetic field, the scattering length is fixed, and this had led to a rather limited range of interaction strengths in experiments. However, it has been predicted that a magnetically tunable Feshbach resonance could be used to strongly modify scattering lengths [1]. We have observed such a Feshbach resonance in collisions of ultracold 85Rb(f =2, mf=−2) atoms in a magnetic field B. From our measured resonance position and width, we infer that the scattering length a2,−2 for collisions of these atoms has the dispersive resonance form.
We have measured the elastic-scattering cross section of 87Rb^{87}\mathrm{Rb}87Rb atoms in the \ensuremath{\Vert}F=1,mF{\mathit{m}}_{\mathit{F}}mF​=-1〉 ground state at 25 \ensuremath{\mu}K. The cross section is almost purely s wave at these temperatures and has a value of (5.4\ifmmode\pm\else\textpm\fi{}1.3)\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}12}$ cm2{\mathrm{cm}}^{2}cm2. We have searched for the predicted Feshbach-type resonances in the elastic cross section [Tiesinga et al., Phys. Rev. A 46, 1167 (1992)] as a function of magnetic field. There are no resonances with a magnetic-field width \ensuremath{\ge}2 G over a magnetic-field range of 15--540 G.
The properties of Bose-Einstein condensed gases can be strongly altered by tuning the external magnetic field near a Feshbach resonance. Feshbach resonances affect elastic collisions and lead to the observed modification of the scattering length. However, as we report here, the observed rate of inelastic collisions was strongly enhanced in a sodium Bose-Einstein condensate when the scattering length was tuned to both larger or smaller values than the off-resonant value. These strong losses impose severe limitations for using Feshbach resonances to tune the properties of Bose-Einstein condensates.
A magnetic field-dependent Feshbach resonance has been observed in the elastic scattering collision rate between atoms in the $F\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2,M\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\ensuremath{-}2$ state of 85Rb{}^{85}\mathrm{Rb}85Rb. Changing the magnetic field by several Gauss caused the collision rate to vary by a factor of 104{0}^{4}04, and the sign of the scattering length could be reversed. The resonance peak is at 155.2(4) G and its width is 11.6(5) G. From these results we extract much improved values for the three quantities that characterize the interaction potential: The van der Waals coefficient C6{C}_{6}C6​, the singlet scattering length aS{a}_{S}aS​, and the triplet scattering length aT{a}_{T}aT​.