SCIENCE - New technique excites atoms and molecules using pulsed laser

The best method to obtain the most precise information on the inner structure of atoms and molecules is to excite them by means of resonant laser light. Unfortunately, just this laser light (above a certain intensity) can lead to measurable modifications within the atom's electron shell. Scientists of the Physikalisch-Technische Bundesanstalt (PTB) have now shown experimentally how to prevent such "light shifts". This confirms the advantages of "hyper" Ramsey excitation that had already been predicted theoretically. This method can make their optical ytterbium atomic clocks even more accurate. Furthermore, "hyper" Ramsey excitation can be helpful in numerous applications where the focus lies on a precise, controlled interaction between atoms and laser light. The results have been published in the current issue of the scientific journal Physical Review Letters.

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