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

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)

Experiments with a 39 K Bose-Einstein condensate with tunable interactions

G. Roati, Jacopo Catani, Chiara D’Errico, M. Fattori, Matteo Zaccanti, Michele Modugno, Andrea Simoni, M. Inguscio, Giovanni Carlo Modugno

Published Jun 1, 2007• 0 citations
Publisher

Abstract

We produce a novel Bose-Einstein condensate composed of39K atoms. Condensation of this species was so far prevented by a naturally small and negative scattering length. We report on the properties of the39K Bose-Einstein condensates, and on ongoing experiments on atom interferometry.
DOI
10.1109/cleoe-iqec.2007.4386732

Related papers

K39 Bose-Einstein Condensate with Tunable Interactions

G. Roati, Matteo Zaccanti, Chiara D’Errico +5 more

We produce a Bose-Einstein condensate of 39K atoms. Condensation of this species with a naturally small and negative scattering length is achieved by a combination of sympathetic cooling with 87Rb and direct evaporation, exploiting the magnetic tuning of both inter- and intraspecies interactions at Feshbach resonances. We explore the tunability of the self-interactions by studying the expansion and the stability of the condensate. We find that a 39K condensate is interesting for future experiments requiring a weakly-interacting Bose gas.

arXiv:cond-mat/0703714•Physical Review Letters•Jul 6, 2007•239 citations

Atom Interferometry with a Weakly Interacting Bose Einstein Condensate

M. Fattori, Chiara D’Errico, G. Roati +5 more

We demonstrate trapped atom interferometry with a weakly interacting Bose Einstein condensate. Atomic scattering length is tuned almost to zero by means of a broad magnetic Feshbach resonance and interaction induced decoherence results strongly suppressed.

Frontiers in Optics•Jan 1, 2008•4 citations

Direct evaporative cooling of 39 K atoms to Bose-Einstein condensation

Manuele Landini, Sanjukta Roy, G. Roati +4 more

We report the realization of a Bose-Einstein condensate of ${}^{39}$K atoms without the aid of an additional atomic coolant. Our route to Bose-Einstein condensation comprises sub-Doppler laser cooling of large atomic clouds with more than ${10}^{10}$ atoms and evaporative cooling in an optical dipole trap where the collisional cross section can be increased using magnetic Feshbach resonances. Large condensates with almost ${10}^{6}$ atoms can be produced in less than 15 s. Our achievements eliminate the need for sympathetic cooling with Rb atoms, which was the usual route implemented until now due to the unfavorable collisional property of ${}^{39}$K. Our findings simplify the experimental setup for producing Bose-Einstein condensates of ${}^{39}$K atoms with tunable interactions, which have a wide variety of promising applications, including atom interferometry to studies on the interplay of disorder and interactions in quantum gases.

arXiv:1207.4713•Physical Review A•Sep 20, 2012•41 citations

Stability of Atomic Bose-Einstein Condensate with Negative Scattering Length

Weiping Zhang, Barry C. Sanders, A. Mann

We discuss the stability of a small-scale Bose-Einstein condensate with negative scattering length. The stable state is found by obtaining the appropriate basis using self-consistent field theory for an attractive one-dimensional potential.

Journal de Physique I•Nov 1, 1996•2 citations

Bose-Einstein Condensation in Trapped Atomic Gases

Yu. Kagan, Georgy V. Shlyapnikov, Jook T. M. Walraven

We discuss Bose-Einstein condensation in a trapped atomic gas and analyze how the sign of the scattering length a and the ratio \ensuremath{\eta} of the interaction between particles to the level spacing in the trap influence the behavior of the condensate wave function ${\ensuremath{\psi}}_{0}$. We find that for $a<0$ and $\ensuremath{\eta}\ensuremath{\ll}1$ it is possible to form a metastable Bose condensate, with a long characteristic lifetime with respect to contraction and transitions of particles to excited trap states. For $\ensuremath{\eta}\ensuremath{\gg}1$ a negative scattering length prevents the formation of the condensate. If $a>0$, then an increase of density is accompanied by the evolution of ${\ensuremath{\psi}}_{0}$ to a comparatively wide quasihomogeneous distribution.

Physical Review Letters•Apr 8, 1996•171 citations

Stable 85Rb Bose-Einstein Condensates with Widely Tunable Interactions

Simon L. Cornish, N. R. Claussen, Jacob Roberts +2 more

Bose-Einstein condensation has been achieved in a magnetically trapped sample of 85Rb atoms. Long-lived condensates of up to 10(4) atoms have been produced by using a magnetic-field-induced Feshbach resonance to reverse the sign of the scattering length. This system provides new opportunities for the study of condensate physics. The variation of the scattering length near the resonance has been used to magnetically tune the condensate self-interaction energy over a wide range, extending from strong repulsive to large attractive interactions. When the interactions were switched from repulsive to attractive, the condensate shrank to below our resolution limit, and after approximately 5 ms emitted a burst of high-energy atoms.

arXiv:cond-mat/0004290•Physical Review Letters•Aug 28, 2000•899 citations
We produce a Bose-Einstein condensate of 39K atoms. Condensation of this species with a naturally small and negative scattering length is achieved by a combination of sympathetic cooling with 87Rb and direct evaporation, exploiting the magnetic tuning of both inter- and intraspecies interactions at Feshbach resonances. We explore the tunability of the self-interactions by studying the expansion and the stability of the condensate. We find that a 39K condensate is interesting for future experiments requiring a weakly-interacting Bose gas.
We report the realization of a Bose-Einstein condensate of 39{}^{39}39K atoms without the aid of an additional atomic coolant. Our route to Bose-Einstein condensation comprises sub-Doppler laser cooling of large atomic clouds with more than 1010{10}^{10}1010 atoms and evaporative cooling in an optical dipole trap where the collisional cross section can be increased using magnetic Feshbach resonances. Large condensates with almost 106{10}^{6}106 atoms can be produced in less than 15 s. Our achievements eliminate the need for sympathetic cooling with Rb atoms, which was the usual route implemented until now due to the unfavorable collisional property of 39{}^{39}39K. Our findings simplify the experimental setup for producing Bose-Einstein condensates of 39{}^{39}39K atoms with tunable interactions, which have a wide variety of promising applications, including atom interferometry to studies on the interplay of disorder and interactions in quantum gases.
We discuss Bose-Einstein condensation in a trapped atomic gas and analyze how the sign of the scattering length a and the ratio \ensuremath{\eta} of the interaction between particles to the level spacing in the trap influence the behavior of the condensate wave function ${\ensuremath{\psi}}_{0}$. We find that for a<0a<0a<0 and $\ensuremath{\eta}\ensuremath{\ll}1$ it is possible to form a metastable Bose condensate, with a long characteristic lifetime with respect to contraction and transitions of particles to excited trap states. For $\ensuremath{\eta}\ensuremath{\gg}1$ a negative scattering length prevents the formation of the condensate. If a>0a>0a>0, then an increase of density is accompanied by the evolution of ${\ensuremath{\psi}}_{0}$ to a comparatively wide quasihomogeneous distribution.
Bose-Einstein condensation has been achieved in a magnetically trapped sample of 85Rb atoms. Long-lived condensates of up to 10(4) atoms have been produced by using a magnetic-field-induced Feshbach resonance to reverse the sign of the scattering length. This system provides new opportunities for the study of condensate physics. The variation of the scattering length near the resonance has been used to magnetically tune the condensate self-interaction energy over a wide range, extending from strong repulsive to large attractive interactions. When the interactions were switched from repulsive to attractive, the condensate shrank to below our resolution limit, and after approximately 5 ms emitted a burst of high-energy atoms.