Experiments With Ion Traps

The ion trap and laser laboratory is the only laboratory of this kind in Spain. We started to build the laboratory in March 2012 in the framework of the project TRAPSENSOR funded by the European Research Council. We also got funding from the Spanish Ministry of Economy and Competitiveness, and the regional Government of Andalusia. Part of this money comes through the FEDER program and the University of Granada.


Figure 1: upper part: sketch representing a Penning trap with parallel plates and an ion oscillating in the axial direction. The current induced by the ion flows through an LC circuit, which is resonant with the oscillation frequency of the ion. Lower part: Sketch of the system proposed to use the fluorescence photons from a single laser-cooled 40Ca+ ion instead of an electronic circuit. The 40Ca+ ion is cooled to the Doppler limit.

The most remarkable aim envisaged in the laboratory is to build a system to couple two ions stored in different traps. The traps have a common electrode in order to make the electric charge induced by the ion flow between the traps. This idea was proposed in the nineties by D.J. Heinzen and D.J. Wineland but has not been realized so far. A successful completion of this system will allow substituting electronic detection, shown in the upper part of Fig. 1, by the detection of fluorescence photons (lower part in Fig. 2) and this will increase the sensitivity in mass spectrometry, which is important to perform measurements on superheavy elements produced in fusion-evaporation reactions at linear accelerators such at GSI-Darmstadt or to use the mass of specific nuclei for neutrino physics The left side of Fig. 2 shows a laser-cooled 40Ca+ ion in one of the ion traps built at the University of Granada. The right side of the figure shows the geometry of the open-ring trap built at the University for these kinds of experiments


Figure 2: Left: fluorescence photons from a laser 40Ca+ ion collected with an Electron Multiplier CCD camera. The ions are created inside the trap shown on the right side and they are laser-cooled. The fluorescence photons collected within a certain solid angle are collimated to be register in to the EMCCD for the studies.