Long-lifetime optical trapping of a ⁴⁰Ca⁺ ion

We have experimentally achieved the all-optical trapping of a 40 Ca + ion for the first time. An optical dipole trap was established using a high-power, far-detuned, tightly focused laser with a wavelength of 532 nm. The single 40 Ca + ion was trapped without any radio-frequency (RF) fields and demonstrated a long lifetime of over 3 seconds. In this experiment, we implemented several measures to improve the optical trapping probability, including focusing the dipole beam waist near the diffraction limit, precisely compensating for stray electric fields, and mitigating electron shelving in metastable states. The optical trapping of a 40 Ca + ion eliminates the influence of micromotion induced by RF fields, potentially paving the way for the development of all-optical trapping ion optical clocks.