Thermally assisted flux flow in MgB2: strong magnetic field dependence of the activation energy

• Published in: Philosophical magazine (Abingdon, England) Vol. 85; no. 16; pp. 1783 - 1790
• Main Authors: Sidorenko, A., Zdravkov, V., Ryazanov, V., Horn, S., Klimm, S., Tidecks, R., Wixforth, A., Koch, Th, Schimmel, Th
• Format: Journal Article
• Language: English
• Published: Taylor & Francis Group 01-06-2005
• ISSN: 1478-6435; 1478-6443
• DOI: 10.1080/14786430500036678

The origin of the resistive transition broadening of superconducting MgB
2
thin films is investigated. Thermally activated flux flow is found to be responsible for the resistivity in the vicinity of the critical temperature. The activation energy for flux motion is observed to have an extraordinary strong dependence on the magnetic field. The results are discussed.