School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332-0430, USA.
Phys Rev Lett. 2011 Jun 3;106(22):223001. doi: 10.1103/PhysRevLett.106.223001. Epub 2011 Jun 2.
We have produced laser-cooled Wigner crystals of 229Th3+ in a linear Paul trap. The magnetic dipole (A) and electric quadrupole (B) hyperfine constants for four low-lying electronic levels and the relative isotope shifts with respect to 232Th3+ for three low-lying optical transitions are measured. Using the hyperfine B constants in conjunction with prior atomic structure calculations, a new value of the spectroscopic nuclear electric quadrupole moment Q=3.11(16) eb is deduced. These results are a step towards optical excitation of the low-lying isomer level in the 229Th nucleus.
我们已经在直线 Paul 阱中制备出了 229Th3+ 的激光冷却 Wigner 晶体。测量了四个低能电子态的磁偶极（A）和电四极（B）超精细常数，以及三个低能光学跃迁相对于 232Th3+ 的同位素位移。利用超精细 B 常数以及之前的原子结构计算，推导出了核电四极矩 Q=3.11(16) eb 的新光谱学值。这些结果是朝着在 229Th 原子核中激发低能同质异能态的光学跃迁迈出的一步。
