We have observed for the first time, crystals of laser-cooled calcium ions in our linear radiofrequency trap built in 2018. The picture below shows the images of one, two and three calcium ions recorded with an EMCCD camera. The separation between the ions in the crystal is about 18 micrometers.

This is a crucial step to perform experiments with a single calcium ion or a linear chain in this setup. We are currently working on our imaging system in order to improve the spatial resolution and the signal-to-noise ratio.