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:1810.08394 · Physical Review A

Dual-species Bose-Einstein condensate of K 41 and Rb 87 in a hybrid trap

A. Burchianti, Chiara D’Errico, S. Rosi, Andrea Simoni, Michele Modugno, C. Fort, F. Minardi

Published Dec 12, 2018• 38 citations
arXivHTMLPDF

Abstract

We report on the production of a $^{41}\mathrm{K}\text{\ensuremath{-}}^{87}\mathrm{Rb}$ dual-species Bose-Einstein condensate in a hybrid trap, consisting of a magnetic quadrupole and an optical dipole potential. After loading both atomic species in the trap, we cool down $^{87}\mathrm{Rb}$ first by magnetic and then by optical evaporation, while $^{41}\mathrm{K}$ is sympathetically cooled by elastic collisions with $^{87}\mathrm{Rb}$. We eventually produce two-component condensates with more than ${10}^{5}$ atoms and tunable species population imbalance. We observe the immiscibility of the quantum mixture by measuring the density profile of each species after releasing them from the trap.

DOI
10.1103/physreva.98.063616

Related papers

Dual-species Bose-Einstein condensate of Rb87 and Cs133

Daniel McCarron, H. W. Cho, Daniel L. Jenkin +2 more

We report the formation of a dual-species Bose-Einstein condensate of $^{87}\mathrm{Rb}$ and $^{133}\mathrm{Cs}$ in the same trapping potential. Our method exploits the efficient sympathetic cooling of $^{133}\mathrm{Cs}$ via elastic collisions with $^{87}\mathrm{Rb}$, initially in a magnetic quadrupole trap and subsequently in a levitated optical trap. The two condensates each contain up to $2\ifmmode\times\else\texttimes\fi{}{10}^{4}$ atoms and exhibit a striking phase separation, revealing the mixture to be immiscible due to strong repulsive interspecies interactions. Sacrificing all the $^{87}\mathrm{Rb}$ during the cooling, we create single-species $^{133}\mathrm{Cs}$ condensates of up to $6\ifmmode\times\else\texttimes\fi{}{10}^{4}$ atoms.

arXiv:1102.1576•Physical Review A•Jul 13, 2011•232 citations

Production of dual species Bose–Einstein condensates of 39K and 87Rb*

Cheng-Dong Mi, Khan Sadiq Nawaz, Peng-Jun Wang +4 more

We report the production of 39K and 87Rb Bose–Einstein condensates (BECs) in the lowest hyperfine states | F = 1,mF = 1 〉 simultaneously. We collect atoms in bright/dark magneto-optical traps (MOTs) of 39K/87Rb to overcome the light-assisted losses of 39K atoms. Gray molasses cooling on the D1 line of the 39K is used to effectively increase the phase density, which improves the loading efficiency of 39K into the quadrupole magnetic trap. Simultaneously, the normal molasses is employed for 87Rb. After the microwave evaporation cooling on 87Rb in the optically plugged magnetic trap, the atoms mixture is transferred to a crossed optical dipole trap, where the collisional properties of the two species in different combinations of the hyperfine states are studied. The dual species BECs of 39K and 87Rb are obtained by further evaporative cooling in an optical dipole trap at a magnetic field of 372.6 G with the background repulsive interspecies scattering length a KRb = 34 a 0 (a 0 is the Bohr radius) and the intraspecies scattering length a K = 20.05a 0.

arXiv:2104.09728•Chinese Physics B•Mar 15, 2021•6 citations

A quantum degenerate mixture of ⁸⁷Rb and ¹³³Cs

Daniel McCarron

This thesis reports the formation of a dual-species Bose-Einstein condensate of $^{87}$Rb and $^{133}$Cs in the same trapping potential. Quantum degenerate mixtures exhibit rich physics inaccessible to single species experiments and provide an ideal starting point for the creation of ultracold dipolar molecules. These molecules offer a wealth of new research avenues including precision metrology, quantum simulation and computation. The experimental method exploits the efficient sympathetic cooling of $^{133}$Cs via elastic collisions with $^{87}$Rb, initially in a magnetic quadrupole trap and subsequently in a levitated optical trap. Evaporative cooling in the dipole trap must compete against a high interspecies three-body inelastic collision rate \mbox{$\sim10^{-25}-10^{-26}$~cm$^{6}/$s}. The two condensates each contain up to \mbox{$2\times10^{4}$} atoms and exhibit a striking phase separation, revealing the mixture to be immiscible due to strong repulsive interspecies interactions. Sacrificing all the $^{87}$Rb during the cooling leads to the creation of single-species $^{133}$Cs condensates of up to \mbox{$6\times10^{4}$} atoms. In addition this thesis reports the observation of an interspecies Feshbach resonance at 181.7(5)~G and the creation of a pure sample of Cs$_{2}$ molecules via magneto-association on the 4(g)4 resonance at 19.8~G. These results represent important steps towards the creation of ultracold polar RbCs molecules.

•Jan 1, 2011•0 citations

Dual-species Bose-Einstein condensates of $^{23}$Na and $^{41}$K with tunable interactions

Jaeryeong Chang, Sung‐Jun Lee, Yoonsoo Kim +2 more

We report the creation of dual-species Bose-Einstein condensates (BECs) of $^{23}$Na and $^{41}$K. Favorable background scattering lengths enable efficient sympathetic cooling of $^{41}$K via forced evaporative cooling of $^{23}$Na in a plugged magnetic trap and an optical dipole trap. The $1/e$ lifetime of the thermal mixture in the stretched hyperfine state exceeds 5 s in the presence of background scattering. At the end of evaporation, we create dual BECs in the immiscible phase, with about $3\times10^5$ $^{23}$Na atoms surrounding $5\times10^4$ $^{41}$K atoms. To further enable the tuning of the interspecies interaction strength, we locate multiple Feshbach resonances at magnetic fields up to 100 G. The broadest $s$-wave resonance located at 73.4(3) G features a favorable width of 1.8(2) G. This work sets the stage for the creation of ultracold gases of strongly dipolar bosonic $^{23}$Na$^{41}$K molecules as well as the exploration of many-body physics in bosonic $^{23}$Na-$^{41}$K mixtures.

arXiv:2312.08186•Dec 13, 2023•0 citations

Tunable dual-species Bose-Einstein condensates of K39 and Rb87

L. J. Wacker, Nils B. Jørgensen, Dorthe Birkmose +6 more

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:1505.07975•Physical Review A•Nov 4, 2015•102 citations

Production of87Rb Bose—Einstein condensates in a hybrid trap

Yafan Duan, Bo-Nan Jiang, Jian-Fang Sun +3 more

We report a rapid evaporative cooling method using a hybrid trap which is composed of a quadrupole magnetic trap and a one-beam optical dipole trap. It contains two kinds of evaporative coolings to reach the quantum degeneracy: initial radio-frequency (RF) enforced evaporative cooling in the quadrupole magnetic trap and further runaway evaporative cooling in the optical dipole trap. The hybrid trap does not require a very high power laser such as that in the traditional pure optical trap, but still has a deep trap depth and a large trap volume, and has better optical access than the normal magnetic trap like the quadrupole-Ioffe-configuration (QUIC) cloverleaf trap. A high trap frequency can be easily realized in the hybrid trap to enhance the elastic collision rate and shorten the evaporative cooling time. In our experiment, pure Bose—Einstein condensates (BECs) with about 1 × 10 5 atoms can be realized in 6 s evaporative cooling in the optical dipole trap.

Chinese Physics B•May 1, 2013•4 citations
We report on the production of a 41K\ensuremath-87Rb^{41}\mathrm{K}\text{\ensuremath{-}}^{87}\mathrm{Rb}41K\ensuremath-87Rb dual-species Bose-Einstein condensate in a hybrid trap, consisting of a magnetic quadrupole and an optical dipole potential. After loading both atomic species in the trap, we cool down 87Rb^{87}\mathrm{Rb}87Rb first by magnetic and then by optical evaporation, while 41K^{41}\mathrm{K}41K is sympathetically cooled by elastic collisions with 87Rb^{87}\mathrm{Rb}87Rb. We eventually produce two-component condensates with more than 105{10}^{5}105 atoms and tunable species population imbalance. We observe the immiscibility of the quantum mixture by measuring the density profile of each species after releasing them from the trap.
We report the formation of a dual-species Bose-Einstein condensate of 87Rb^{87}\mathrm{Rb}87Rb and 133Cs^{133}\mathrm{Cs}133Cs in the same trapping potential. Our method exploits the efficient sympathetic cooling of 133Cs^{133}\mathrm{Cs}133Cs via elastic collisions with 87Rb^{87}\mathrm{Rb}87Rb, initially in a magnetic quadrupole trap and subsequently in a levitated optical trap. The two condensates each contain up to $2\ifmmode\times\else\texttimes\fi{}{10}^{4}$ atoms and exhibit a striking phase separation, revealing the mixture to be immiscible due to strong repulsive interspecies interactions. Sacrificing all the 87Rb^{87}\mathrm{Rb}87Rb during the cooling, we create single-species 133Cs^{133}\mathrm{Cs}133Cs condensates of up to $6\ifmmode\times\else\texttimes\fi{}{10}^{4}$ atoms.
We report the production of 39K and 87Rb Bose–Einstein condensates (BECs) in the lowest hyperfine states | F = 1,mF = 1 〉 simultaneously. We collect atoms in bright/dark magneto-optical traps (MOTs) of 39K/87Rb to overcome the light-assisted losses of 39K atoms. Gray molasses cooling on the D1 line of the 39K is used to effectively increase the phase density, which improves the loading efficiency of 39K into the quadrupole magnetic trap. Simultaneously, the normal molasses is employed for 87Rb. After the microwave evaporation cooling on 87Rb in the optically plugged magnetic trap, the atoms mixture is transferred to a crossed optical dipole trap, where the collisional properties of the two species in different combinations of the hyperfine states are studied. The dual species BECs of 39K and 87Rb are obtained by further evaporative cooling in an optical dipole trap at a magnetic field of 372.6 G with the background repulsive interspecies scattering length a KRb = 34 a 0 (a 0 is the Bohr radius) and the intraspecies scattering length a K = 20.05a 0.
This thesis reports the formation of a dual-species Bose-Einstein condensate of 87^{87}87Rb and 133^{133}133Cs in the same trapping potential. Quantum degenerate mixtures exhibit rich physics inaccessible to single species experiments and provide an ideal starting point for the creation of ultracold dipolar molecules. These molecules offer a wealth of new research avenues including precision metrology, quantum simulation and computation. The experimental method exploits the efficient sympathetic cooling of 133^{133}133Cs via elastic collisions with 87^{87}87Rb, initially in a magnetic quadrupole trap and subsequently in a levitated optical trap. Evaporative cooling in the dipole trap must compete against a high interspecies three-body inelastic collision rate \mbox{∼10−25−10−26\sim10^{-25}-10^{-26}∼10−25−10−26~cm6/^{6}/6/s}. The two condensates each contain up to \mbox{2×1042\times10^{4}2×104} atoms and exhibit a striking phase separation, revealing the mixture to be immiscible due to strong repulsive interspecies interactions. Sacrificing all the 87^{87}87Rb during the cooling leads to the creation of single-species 133^{133}133Cs condensates of up to \mbox{6×1046\times10^{4}6×104} atoms. In addition this thesis reports the observation of an interspecies Feshbach resonance at 181.7(5)~G and the creation of a pure sample of Cs2_{2}2​ molecules via magneto-association on the 4(g)4 resonance at 19.8~G. These results represent important steps towards the creation of ultracold polar RbCs molecules.
Dual-species Bose-Einstein condensates of 23^{23}23Na and 41^{41}41K with tunable interactions
We report the creation of dual-species Bose-Einstein condensates (BECs) of 23^{23}23Na and 41^{41}41K. Favorable background scattering lengths enable efficient sympathetic cooling of 41^{41}41K via forced evaporative cooling of 23^{23}23Na in a plugged magnetic trap and an optical dipole trap. The 1/e1/e1/e lifetime of the thermal mixture in the stretched hyperfine state exceeds 5 s in the presence of background scattering. At the end of evaporation, we create dual BECs in the immiscible phase, with about 3×1053\times10^53×105 23^{23}23Na atoms surrounding 5×1045\times10^45×104 41^{41}41K atoms. To further enable the tuning of the interspecies interaction strength, we locate multiple Feshbach resonances at magnetic fields up to 100 G. The broadest sss-wave resonance located at 73.4(3) G features a favorable width of 1.8(2) G. This work sets the stage for the creation of ultracold gases of strongly dipolar bosonic 23^{23}23Na41^{41}41K molecules as well as the exploration of many-body physics in bosonic 23^{23}23Na-41^{41}41K mixtures.
We present the production of dual-species Bose-Einstein condensates (BECs) of 39K^{39}\mathrm{K}39K and 87Rb^{87}\mathrm{Rb}87Rb. 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 39K^{39}\mathrm{K}39K 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 39K^{39}\mathrm{K}39K with 87Rb^{87}\mathrm{Rb}87Rb. A dark spontaneous force optical trap was used for 87Rb^{87}\mathrm{Rb}87Rb to reduce the losses in 39K^{39}\mathrm{K}39K 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 28.5a028.5{a}_{0}28.5a0​ using an empirical model. This paves the way for dual-species experiments with 39K^{39}\mathrm{K}39K and 87Rb^{87}\mathrm{Rb}87Rb BECs ranging from molecular physics to precision metrology.
We report a rapid evaporative cooling method using a hybrid trap which is composed of a quadrupole magnetic trap and a one-beam optical dipole trap. It contains two kinds of evaporative coolings to reach the quantum degeneracy: initial radio-frequency (RF) enforced evaporative cooling in the quadrupole magnetic trap and further runaway evaporative cooling in the optical dipole trap. The hybrid trap does not require a very high power laser such as that in the traditional pure optical trap, but still has a deep trap depth and a large trap volume, and has better optical access than the normal magnetic trap like the quadrupole-Ioffe-configuration (QUIC) cloverleaf trap. A high trap frequency can be easily realized in the hybrid trap to enhance the elastic collision rate and shorten the evaporative cooling time. In our experiment, pure Bose—Einstein condensates (BECs) with about 1 × 10 5 atoms can be realized in 6 s evaporative cooling in the optical dipole trap.