Modeling Evaporative Cooling of a Dual-species Bose-Einstein Condensate

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.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.

arXiv:1810.08394Physical Review ADec 12, 201838 citations

Dual-species Bose-Einstein condensates of $^{23}$ Na and $^{41}$ K with tunable interactionsDual-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.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:2312.08186Dec 13, 20230 citations

Evaporative Cooling and the Dynamics of a Bose Gas

H. H. Wu, E. Arimondo, Christopher J. Foot

Jan 1, 19960 citations

Towards A Two-Species Bose-Einstein Condensate

E. Arimondo

Kluwer Academic Publishers eBooksDec 11, 20050 citations

A double species 23 Na and 87 Rb Bose–Einstein condensate with tunable miscibility via an interspecies Feshbach resonance

Fudong Wang, Xiaoke Li, Dezhi Xiong +1 more

Abstract We have realized a dual-species Bose–Einstein condensate (BEC) of 23 Na and 87 Rb atoms and observed its immiscibility. Because of the favorable background intra- and inter-species scattering lengths, stable condensates can be obtained via efficient evaporative cooling and sympathetic cooling without the need for fine tuning of the interactions. Our system thus provides a clean platform for studying inter-species interactions–driven effects in superfluid mixtures. With a Feshbach resonance, we have successfully created double BECs with largely tunable inter-species interactions and studied the miscible–immiscible phase transition.Abstract We have realized a dual-species Bose–Einstein condensate (BEC) of 23 Na and 87 Rb atoms and observed its immiscibility. Because of the favorable background intra- and inter-species scattering lengths, stable condensates can be obtained via efficient evaporative cooling and sympathetic cooling without the need for fine tuning of the interactions. Our system thus provides a clean platform for studying inter-species interactions–driven effects in superfluid mixtures. With a Feshbach resonance, we have successfully created double BECs with largely tunable inter-species interactions and studied the miscible–immiscible phase transition.

arXiv:1305.7091Journal of Physics B Atomic Molecular and Optical PhysicsNov 24, 201588 citations

^{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.

Dual-species Bose-Einstein condensates of

^{23}

Na and

^{41}

K with tunable interactions

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}

^{41}

K molecules as well as the exploration of many-body physics in bosonic

^{23}

Na-

^{41}

K mixtures.