Scanning tunneling spectroscopic studies of (100) surface of NdBa2Cu3O7-δ single crystals
|Pintu Das 1, Michael R. Koblischka 1, Thomas Wolf 2, Uwe Hartmann 1|
1. University of Saarbruecken, Institute of Experimental Physics (USAAR), P.O.Box 151150, Saarbrücken 66041, Germany
NdBa2Cu3O7-δ (NdBCO) is an important member of cuprate high-Tc superconductors because of its higher transition temperature as compared to YBa2Cu3O7-δ and critical current density. The similar sizes of the Nd and Ba ions make it possible for Nd ions to replace the Ba ions in the unit cells producing Nd rich phases leading to a spatial Tc variation within the sample. The samples with Nd rich second phase is believed to play an important role in flux pinning . The variation of transition temperature due to the presence of this Nd rich phase is reported to play an important role to explain the increased critical current performance. However, the nature of the basic pinning mechanism needs to be studied in detail. Scanning tunneling spectroscopic studies of these materials are, therefore, necessary to understand the microscopic electronic properties. In this contribution, we report the results of Scanning Tunneling Spectroscopic (STS) measurements performed on the (100) surface of a NdBCO single crystal (Tc = 95.5 K) using a homemade STM at T = 4.2 K. The surface of the crystal was cleaned by chemical etching before doing the measurements .
Presentation: oral at E-MRS Fall Meeting 2004, Symposium E, by Pintu Das
See On-line Journal of E-MRS Fall Meeting 2004
Submitted: 2004-05-09 16:58 Revised: 2009-06-08 12:55