For the first time, researchers place an electron in a dual state—neither freed nor bound

Atoms are composed of electrons moving around a central nucleus to which they are bound. The electrons can also be torn away via the powerful electric field of a laser, overcoming the confining force of their nucleus. A half-century ago, the theorist Walter Henneberger wondered if it were possible to use a laser field to free an electron from its atom without removing it from the nucleus. Many scientists considered it to be impossible. However, it has now been successfully confirmed by physicists from the University of Geneva (UNIGE), Switzerland, and the Max Born Institute (MBI) in Berlin, Germany.