MgB2energy gap determination by scanning tunnelling spectroscopy
| Autor: | Mark Rzchowski, T. W. Heitmann, N. Rogado, C. B. Eom, Michael A. Hayward, J. E. Giencke, D. M. Kim, K. A. Regan, M. K. Haas, J. H. Choi, D. C. Larbalestier, Sang Don Bu, T. He, R. J. Cava, Peter G. Khalifah, Joanna S.G. Slusky |
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| Rok vydání: | 2003 |
| Předmět: |
Superconductivity
Materials science Condensed matter physics Band gap Metals and Alloys Condensed Matter Physics Epitaxy law.invention law Electrical resistivity and conductivity Condensed Matter::Superconductivity visual_art Microscopy Materials Chemistry Ceramics and Composites visual_art.visual_art_medium Ceramic Electrical and Electronic Engineering Thin film Scanning tunneling microscope |
| Zdroj: | Superconductor Science and Technology. 17:237-242 |
| ISSN: | 1361-6668 0953-2048 |
| DOI: | 10.1088/0953-2048/17/2/001 |
| Popis: | We report scanning tunnelling spectroscopy (STS) measurements of the gap properties of both ceramic MgB2 and c-axis oriented epitaxial MgB2 thin films. Both show a temperature dependent zero bias conductance peak and evidence for two superconducting gaps. We report tunnelling spectroscopy of superconductor-insulator-superconductor (S-I-S) junctions formed in two ways in addition to normal metal-insulator-superconductor (N-I-S) junctions. We find a gap Δ = 2.2-2.8 meV, with spectral features and temperature dependence that are consistent between S-I-S junction types. In addition, we observe evidence of a second, larger gap, Δ = 7.2 meV, consistent with a proposed two-hand model. |
| Databáze: | OpenAIRE |
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