Isotope-selective Ion Trapping via SympatheticCooling using a Surface-Electrode Trap with a Holefor Collimated Atomic Loading

We developed a surface-electrode ion trap with a square hole measuring 40 μm for atomic loading. The hole was fabricatedusing anisotropic etching of a silicon substrate and was designed to minimize potential distortion in the trapping region. Byintroducing the atomic beam through the hole, we achieved enhanced isotope selectivity and experimentally demonstrated theselective trapping of calcium isotope ions using an atomic oven. We successfully prepared isotope ion pairs directly from theoven via sympathetic cooling at a rate comparable to that achieved using ablation loading. The sympathetic cooling processoccurred on the order of a few seconds. We demonstrated the direct generation of an ion chain above the through-hole. Thisapproach can be applied for trapping a wide range of ion species using a remarkably simple experimental setup, making itdesirable for several applications such as quantum-charge-coupled-device (QCCD) architectures and precision measurementsof isotope shifts.