A team of U.S. and British physicists reports taking a step toward quantum computing by successfully using a single atomic nucleus as solid-state memory.

Researchers from the U.S. Department of Energy's Lawrence Berkeley National Laboratory, Oxford University and Princeton University said they precisely doped exceptionally pure and isotopically controlled crystals of silicon with phosphorus atoms. Quantum information was processed in the phosphorus electrons, transferred to the phosphorus nuclei and then subsequently transferred back to the electrons.

The scientists said that was the first demonstration that a single atomic nucleus can serve as quantum computational memory.

"In this exciting collaboration �� we have reported on a very important demonstration of coherent information transfer between the electron spin (processing qubit) and the nuclear spin (memory qubit) of phosphorus atoms in isotopically enriched silicon crystals," said study co-author Thomas Schenkel, a physicist in Berkeley Lab's Accelerator and Fusion Research Division.

"The electron spin information was faithfully stored in the nuclear spin for nearly two seconds (thousands of times longer than ever reported previously) and then transferred back to the electron spin with about 90-percent fidelity," Schenkel said.

The experiment is reported in the Oct. 23 issue of the journal Nature.