In 2015, a Paul trap experiment with a single ion laser-cooled to the Doppler limit was reached. This trap has a non-conventional geometry, which was taken as reference for the design and construction of the double-microtrap system. The trap is made of two sets of three concentric rings centered on the z-axis. A description of the setup can be found here.

The experiments performed in this setup have provided us the characterization of a single laser-cooled 40Ca+ ion as an optical detector of electric signals. In 2017, a manuscript reporting these measurements has been published in Scientific Reports. Further characterization measurements were realized with two 40Ca+ ions in order to extend the method to Penning traps. These results have been reported in a special issue of Journal of Modern Optics.