Bohr's theoretical model suggested electrons travel in orbits around the atom's nucleus as planets orbit a star. But that was eventually displaced by quantum mechanics, which showed electrons don't have precise positions, but are instead distributed in wave-like patterns.

"In a sufficiently large system, the quantum effects at the atomic scale can transition into the classical mechanics found in Bohr's model," said Rice University Professor Barry Dunning. "Using highly excited Rydberg atoms and a series of pulsed electric fields, we were able to manipulate the electron motion and create circular, planet-like states."

He said the research shows electrons remain localized for several orbits and behave much as classical particles -- a finding that has potential applications in next-generation computers and in the study of classical and quantum chaos.

The study that included Rice researchers Jeffery Mestayer, Brendan Wyker and Jim Lancaster; Oak Ridge National Laboratory's Carlos Reinhold; and the Vienna University of Technology's Shuhei Yoshida and Joachim Burgdorfer appears online in the journal Physical Review Letters.