Find in Library

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 3×10^{5} ^{23}Na atoms surrounding 5×10^{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.