For conventional ion traps, the trapping potential is close to independent of the electronic state, providing confinement for ions dependent primarily on their charge-to-mass ratio $Q/m$. In contrast, storing ions within an optical dipole trap results in state-dependent confinement. Here we experimentally study optical dipole potentials for ${}^{138}\mathrm{Ba}^{+}$ ions stored within two distinctive traps operating at 532 and 1064 nm. We prepare the ions in either the electronic ground ($6S_{1/2}$) or one of the metastable excited states ($5D_{3/2}$ or $5D_{5/2}$) and probe the relative strength and polarity of the potential. On the one hand, we apply our findings to selectively remove ions from a Coulomb crystal, despite all ions sharing the same $Q/m$. On the other hand, we deterministically purify the trapping volume from parasitic ions in higher-energy orbits, resulting in reliable isolation of Coulomb crystals down to a single ion within a radio-frequency trap.

中文翻译：

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通过状态选择光势捕获，整形和隔离离子库仑晶体

对于常规离子阱，阱势几乎与电子态无关，从而主要根据离子的荷质比对离子进行限制 $问/米$。相反，将离子存储在光学偶极阱中会导致状态限制。在这里，我们通过实验研究光偶极子电势${}^{138}巴^{+}$离子存储在工作于532和1064 nm的两个不同的陷阱中。我们在电子地面上准备离子（$6{\mathrm{小号}}_{\mathrm{1个}/2}$）或亚稳态激发态之一（$5d_{3/2}$ 要么 $5d_{5/2}$）并探查电位的相对强度和极性。一方面，我们运用我们的发现从库仑晶体中选择性去除离子，尽管所有离子都共享相同的离子。$问/米$。另一方面，我们确定性地从高能轨道中的寄生离子中纯化了捕集体积，从而将库仑晶体可靠地隔离到了射频陷阱中的单个离子。