Rydberg carbon clusters prepared by pulsed field recombination

The technique of pulsed field recombination is used to recombine a free electron with carbon cation clusters, ranging from C60+ to C50+. It is shown that after recombination the electron is left in a highly excited state. The recombination method produces a Rydberg state (n∼180) in a large carbon cluster, such as C60, with an electronic energy spread of ∼1 K. We measured a recombination efficiency of ∼6%.