Work

The properties of atoms are determined by laws of quantum mechanics that say they can have only fixed energy levels and that electromagnetic radiation with certain frequencies is emitted or absorbed when there are transitions among different energy levels. Opportunities to study the properties and spectrums of atoms are improved if individual atoms can be isolated under constant conditions for longer periods. In the 1950s Wolfgang Paul developed a method for using electrical currents and electromagnetic fields to capture charged atoms—ions—in a trap.