Experimental Setup

A schematic overview of the experimental setup is given in figure 1. The calcium atoms are evaporated in the oven, after which they are collimated before entering the Zeeman slower. In the Zeeman slower all atoms are slowed down from velocities up to a 1000 m/s down to a narrow velocity distribution around 50 m/s. After the Zeeman slower the isotope that we want to trap is deflected from the main beam and is transported to a standard magneto-optical trap (MOT) where its concentration is determined by measuring the fluorescence.

The trapping chamber and oven have been designed and/or built at the KVI. The Zeeman slower is also designed and built at the KVI. Check out the pictures of more then six thousand copper windings over here. The laserlight we need for the cooling and trapping of calcium is at a wavelength of 423 nm. We use a frequency doubled diode laser (Toptica). In order to get enough blue laser power we first amplify the infrared (846 nm) light in a tapered amplifier. The typical 423 nm laser intensity at moments the machine is running like it should is about 60 mW, in the future we will certainly need more. We have observed up to 75 mW of blue light with this laser system.