Dutta Sourav, Sawant Rahul, Rangwala S A
Raman Research Institute, C. V. Raman Avenue, Sadashivanagar, Bangalore 560080, India.
Phys Rev Lett. 2017 Mar 17;118(11):113401. doi: 10.1103/PhysRevLett.118.113401. Epub 2017 Mar 16.
We experimentally demonstrate cooling of trapped ions by collisions with cotrapped, higher-mass neutral atoms. It is shown that the lighter ^{39}K^{+} ions, created by ionizing ^{39}K atoms in a magneto-optical trap (MOT), when trapped in an ion trap and subsequently allowed to cool by collisions with ultracold, heavier ^{85}Rb atoms in a MOT, exhibit a longer trap lifetime than without the localized ^{85}Rb MOT atoms. A similar cooling of trapped ^{85}Rb^{+} ions by ultracold ^{133}Cs atoms in a MOT is also demonstrated in a different experimental configuration to validate this mechanism of ion cooling by localized and centered ultracold neutral atoms. Our results suggest that the cooling of ions by localized cold atoms holds for any mass ratio, thereby enabling studies on a wider class of atom-ion systems irrespective of their masses.
我们通过实验证明了被俘获离子与共俘获的、质量更大的中性原子碰撞时的冷却现象。结果表明，在磁光阱（MOT）中通过电离(^{39}K)原子产生的较轻的(^{39}K^{+})离子，当被捕获在离子阱中并随后通过与MOT中极冷的、较重的(^{85}Rb)原子碰撞而冷却时，其阱寿命比没有局部(^{85}Rb)MOT原子时更长。在不同的实验配置中，还证明了MOT中极冷的(^{133}Cs)原子对被俘获的(^{85}Rb^{+})离子的类似冷却，以验证这种通过局部和居中的极冷中性原子进行离子冷却的机制。我们的结果表明，局部冷原子对离子的冷却适用于任何质量比，从而能够对更广泛的一类原子 - 离子系统进行研究，而不论它们的质量如何。
