Precise studies of Feshbach resonance crossing experiments in Bose-Einstein condensates

We present the production of dual-species Bose-Einstein condensates (BECs) of $^{39}\mathrm{K}$ and $^{87}\mathrm{Rb}$ . Preparation of both species in the $\left|F=1,{m}_{F}=\ensuremath{-}1\right\ensuremath{\rangle}$ state enabled us to exploit a total of three Feshbach resonances, which allows for simultaneous Feshbach tuning of the $^{39}\mathrm{K}$ intraspecies and the $^{39}\mathrm{K}\text{\ensuremath{-}}^{87}\mathrm{Rb}$ interspecies scattering length. Thus dual-species Bose-Einstein condensates were produced by sympathetic cooling of $^{39}\mathrm{K}$ with $^{87}\mathrm{Rb}$ . A dark spontaneous force optical trap was used for $^{87}\mathrm{Rb}$ to reduce the losses in $^{39}\mathrm{K}$ due to light-assisted collisions in the optical trapping phase, which can be of benefit for other dual-species experiments. The tunability of the scattering length was used to perform precision spectroscopy of the interspecies Feshbach resonance located at 117.56(2) G and to determine the width of the resonance to 1.21(5) G by rethermalization measurements. The transition region from miscible to immiscible dual-species condensates was investigated and the interspecies background scattering length was determined to $28.5{a}_{0}$ using an empirical model. This paves the way for dual-species experiments with $^{39}\mathrm{K}$ and $^{87}\mathrm{Rb}$ BECs ranging from molecular physics to precision metrology.We present the production of dual-species Bose-Einstein condensates (BECs) of $^{39}\mathrm{K}$ and $^{87}\mathrm{Rb}$. Preparation of both species in the $\left|F=1,{m}_{F}=\ensuremath{-}1\right\ensuremath{\rangle}$ state enabled us to exploit a total of three Feshbach resonances, which allows for simultaneous Feshbach tuning of the $^{39}\mathrm{K}$ intraspecies and the $^{39}\mathrm{K}\text{\ensuremath{-}}^{87}\mathrm{Rb}$ interspecies scattering length. Thus dual-species Bose-Einstein condensates were produced by sympathetic cooling of $^{39}\mathrm{K}$ with $^{87}\mathrm{Rb}$. A dark spontaneous force optical trap was used for $^{87}\mathrm{Rb}$ to reduce the losses in $^{39}\mathrm{K}$ due to light-assisted collisions in the optical trapping phase, which can be of benefit for other dual-species experiments. The tunability of the scattering length was used to perform precision spectroscopy of the interspecies Feshbach resonance located at 117.56(2) G and to determine the width of the resonance to 1.21(5) G by rethermalization measurements. The transition region from miscible to immiscible dual-species condensates was investigated and the interspecies background scattering length was determined to $28.5{a}_{0}$ using an empirical model. This paves the way for dual-species experiments with $^{39}\mathrm{K}$ and $^{87}\mathrm{Rb}$ BECs ranging from molecular physics to precision metrology.

arXiv:1505.07975Physical Review ANov 4, 2015102 citations

Observation of Feshbach resonances in a Bose–Einstein condensate

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

NatureMar 1, 19982,094 citations

Precision Feshbach spectroscopy of ultracold Cs2

Cheng Chin, Vladan Vuletić, Andrew J. Kerman +4 more

We have observed and located more than 60 magnetic field-induced Feshbach resonances in ultracold collisions of ground-state $^{133}\mathrm{Cs}$ atoms. Multiple extremely weak Feshbach resonances associated with $g$ -wave molecular states are detected through variations in the radiative collision cross sections. The Feshbach spectroscopy allows us to determine the interactions between ultracold cesium atoms and the molecular energy structure near the dissociation continuum with unprecedented precision. Our work not only represents a very successful collaboration of experimental and theoretical efforts, but also provides essential information for cesium Bose-Einstein condensation, ${\mathrm{Cs}}_{2}$ molecules, and atomic clock experiments.We have observed and located more than 60 magnetic field-induced Feshbach resonances in ultracold collisions of ground-state $^{133}\mathrm{Cs}$ atoms. Multiple extremely weak Feshbach resonances associated with $g$-wave molecular states are detected through variations in the radiative collision cross sections. The Feshbach spectroscopy allows us to determine the interactions between ultracold cesium atoms and the molecular energy structure near the dissociation continuum with unprecedented precision. Our work not only represents a very successful collaboration of experimental and theoretical efforts, but also provides essential information for cesium Bose-Einstein condensation, ${\mathrm{Cs}}_{2}$ molecules, and atomic clock experiments.

Physical Review ASep 3, 2004163 citations

Feshbach resonances in Bose-Einstein condensates

JM Johnny Vogels

Jan 1, 19992 citations

Feshbach resonances in atomic Bose–Einstein condensates

E.A.H. Timmermans

Physics ReportsJul 1, 1999609 citations

We present the production of dual-species Bose-Einstein condensates (BECs) of

^{39}\mathrm{K}

and

^{87}\mathrm{Rb}

. Preparation of both species in the $\left|F=1,{m}_{F}=\ensuremath{-}1\right\ensuremath{\rangle}$ state enabled us to exploit a total of three Feshbach resonances, which allows for simultaneous Feshbach tuning of the

^{39}\mathrm{K}

intraspecies and the $^{39}\mathrm{K}\text{\ensuremath{-}}^{87}\mathrm{Rb}$ interspecies scattering length. Thus dual-species Bose-Einstein condensates were produced by sympathetic cooling of

^{39}\mathrm{K}

with

^{87}\mathrm{Rb}

. A dark spontaneous force optical trap was used for

^{87}\mathrm{Rb}

to reduce the losses in

^{39}\mathrm{K}

due to light-assisted collisions in the optical trapping phase, which can be of benefit for other dual-species experiments. The tunability of the scattering length was used to perform precision spectroscopy of the interspecies Feshbach resonance located at 117.56(2) G and to determine the width of the resonance to 1.21(5) G by rethermalization measurements. The transition region from miscible to immiscible dual-species condensates was investigated and the interspecies background scattering length was determined to

28.5{a}_{0}

using an empirical model. This paves the way for dual-species experiments with

^{39}\mathrm{K}

and

^{87}\mathrm{Rb}

BECs ranging from molecular physics to precision metrology.

We have observed and located more than 60 magnetic field-induced Feshbach resonances in ultracold collisions of ground-state

^{133}\mathrm{Cs}

atoms. Multiple extremely weak Feshbach resonances associated with

g

-wave molecular states are detected through variations in the radiative collision cross sections. The Feshbach spectroscopy allows us to determine the interactions between ultracold cesium atoms and the molecular energy structure near the dissociation continuum with unprecedented precision. Our work not only represents a very successful collaboration of experimental and theoretical efforts, but also provides essential information for cesium Bose-Einstein condensation,

{\mathrm{Cs}}_{2}

molecules, and atomic clock experiments.