COHERENT EXCITATION OF NORMAL-MODES IN A STRING OF CA+ IONS

Crystal structures of Calcium ions have been prepared in a linear Paul trap and their collective motion excited with resonant rf-fields. The trapped ions are laser-cooled and images of the fluorescing ions are obtained with a CCD camera and show high spatial resolution. Crystals with up to 15 ions arrange in a linear string and their eigenmodes can subsequently be selectively excited. The collective motion of the str ing can then be observed via the CCD images. (C) 1998 Optical Society of America.