19 January 1996
Vol 271, Issue 5247

About The Cover

Scanning superconducting quantum interface device microscope image of the magnetic field trapped in thin-film rings of a thallium-based cuprate high-temperature superconductor. The lower right control ring is in the one flux quantum state, the center ring is in the one-half flux quantum state, and the other two rings are in the zero flux quantum state. This result provides strong support for d-wave pairing symmetry in high-temperature cuprate superconductors. See 329 and News story on 288. [Image: Cliff Pickover]