Upper critical magnetic fields of Bi2Sr2CuO6 single crystals

✍ Scribed by J.W Chen

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 390 KB
• Volume: 225
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(94)90726-9

✦ Synopsis

The upper critical magnetic fields of Bi2Sr2CuOe single crystals with the applied magnetic fields H parallel to the ab-plane, Hc2(ab), and perpendicular to the ab-plane, Ha(c), have been determined from the AC electrical resistivity measurements up to 8 T. Both He2 (ab) and Hc2 ( c ) exhibit positive curvature as a function of temperature T for He2 < 2 T which is much pronounced in H¢2(ab). The initial slopes ( -rHea~tiT)tea determined from the linear portion of the He2 versus T curves have the values of 5.0 T/K for H~2 (ab) and 1.6 T/K for Ha (c). Both Ha (ab) and He2 (c) data can be fiued very well by the conventional Werthamer, Helfand, Hobenberg and Maki (WHHM) theory in the minimum paramagnetic limit (;t,.--oo) using the experimental values of the initial slopes ( -dH¢2/dT ) tea and Tc's and indicates an ordinary type superconductivity in this system. The value of the anisotropic ratio obtained from the H¢2 (T) data and the ( -dHe2/dT ) Tea data is about 3.3.