Nonselective Paul Ion Trap Loading With A Light-Emitting Diode

We demonstrate a simple nonisotope-selective method for ion trap loading, which is based on the irradiation of trap electrodes precoated with materials with a low work function by a light-emitting diode (LED). Photoelectrons emitted from the electrode surface and accelerated in the trap electric field ionize the atomic beam inside the trap, which results in the trap loading. We studied Y2O3 and Mg coatings for the trap electrodes and experimentally demonstrated trapping of single Mg-24(+) ions as well as large ion crystals composed of up to 10(3) particles using a 400nm LED. This method can be readily implemented in a variety of applications where simplicity, compactness, and robustness are critical, such as in portable ion frequency standards and commercial ion-based devices, for example. Possible modifications of this technique aimed for selective loading, reduction of induced electric stray fields, and getting rid of atomic oven are also discussed.