Like signals moving along a coaxial cable, molecules in a new scheme are guided along a central wire inside a metal tube.
Molecules are notoriously difficult to guide and trap.
Nevertheless, physicists and chemists have devised increasingly clever methods to control molecular motion. Now a team reports in the 25 September PRL that they have successfully sent a common, but previously unmanageable, class of molecules spiraling along a wire. Although this method can't yet trap the molecules, the team hopes the breakthrough will soon lead to doughnut-shaped molecular storage rings. To trap atoms, researchers use lasers and exploit the atoms' simple quantum energy level structure. If the field is strong enough, however, it can force more alignment of the dipole and prevent even a rotationally excited molecule from rotating.