Transport anisotropies of c. ab104 to 105 were measured for superconducting and nonsuperconducting Bi2+xSr2-yCuO6± crystals. In superconducting samples ab increases linearly with temperature from just above Tc7 to 700 K. The implication of the ab results is that classical electron-phonon scattering mechanisms are inadequate. The anisotropy and Tc for various layered superconductor systems are compared. In all crystals studied c is nonmetallic, varying as a power law T- , ±0.51.
|Number of pages||4|
|Journal||Physical Review B|
|State||Published - 1 Jan 1990|