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arXiv · 1901.02218

Vortex glass-liquid transition and activated flux motion in an epitaxial, super-conducting NdFeAs(O,F) thin film

J. Hänisch·K. Iida·T. Ohmura·T. Matsumoto·T. Hatano·M. Langer·S. Kauffmann-Weiss·H. Ikuta·B. Holzapfel
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Abstract

An epitaxial NdFeAs(O,F) thin film of 90 nm thickness grown by molecular beam epitaxy on MgO single crystal with Tc = 44.2 K has been investigated regarding a possible vortex glass-liquid tran-sition. The voltage-current characteristics show excellent scalability according to the vortex-glass model with a static critical exponent {\nu} of around 1.35 and a temperature-dependent dynamic exponent z increasing from 7.8 to 9.0 for the investigated temperature range. The large and non-constant z values are discussed in the frame of 3D vortex glass, thermally activated flux motion, and inhomogeneity broadening.

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J. Hänisch, K. Iida, T. Ohmura, T. Matsumoto, T. Hatano, M. Langer, S. Kauffmann-Weiss, H. Ikuta, B. Holzapfel. 2019-01-08. Vortex glass-liquid transition and activated flux motion in an epitaxial, super-conducting NdFeAs(O,F) thin film. https://doi.org/10.1557/mrc.2018.207

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