New ion trap for frequency standard applications

Abstract

We have designed a novel linear ion trap which permits storage of a large number of ions with reduced susceptibility to the second-order Doppler effect caused by the rf confining fields. This new trap should store about 20 times the number of ions as a conventional rf trap with no corresponding increase in second-order Doppler shift from the confining field. In addition the sensitivity of this shift to trapping parameters, i.e., rf voltage, rf frequency, and trap size, is greatly reduced.