Tunneling spectroscopy on Bi2Sr2CaCu2O8+δ single crystals at T = 4.2 K

✍ Scribed by L. Buschmann; M. Boekholt; G. Güntherodt

• Publisher: Elsevier Science
• Year: 1992
• Tongue: English
• Weight: 481 KB
• Volume: 203
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(92)90509-b

✦ Synopsis

We report on N-I-S point contact and S-I-S break junction tunneling measurements at T=4.2 K on Bi2Sr2CaCu2Os+6 single crystals (Tc = 78-86 K). For the latter experiments, the breaking of the crystal was done in liquid He atmosphere in order to produce clean surfaces. The superconducting energy gap scales with Tc within the error bars of the experiments. The S-I-S break junction on Bi2Sr2CaCu2Os+6 single crystals identifies the direction of the tunneling current. The energy gap is found to be anisotropic: parallel to the CuO2-planes an average gap value of 2A u =45 +_ 3 meV is obtained. Perpendicular to those planes the average gap value amounts to 2d± = 26 + 3 meV. Hence, there result ratios of 2A~ (0)/kBTc = 5.9 + 0.4 and 2A± (0)/keTc= 3.6 + 0.5.