A cloud of 40Ca+is successfully trapped and cooled using the radiation of a red-detuned 397 nm laser beam and a resonant 866 nm laser beam in our prototype linear ion trap,which was designed and constructed for studying quantum information processing.We have characterized the size of the ion cloud,estimating the temperature to be in the order of milli-Kelvins.
This paper reports that a cloud of laser-cooled ^40Ca^＋ is successfully trapped and manipulated in the home-built linear ion trap constructed for quantum information processing （QIP）. The frequency of the secular motion and the space charge density of the ion cloud are measured, which help knowing the characteristic of the trapping potential and are the prerequisite of QIP with the trapped ions.
