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arXiv · 1507.03318

Localized High Frequency Electrodynamic Behavior of Optimally-doped Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ Single Crystal films

Tamin Tai·Behnood G. Ghamsari·J. H. Kang·S. Lee·C. B. Eom·Steven M. Anlage
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Abstract

Localized high frequency (several GHz) electrodynamic properties of a high quality epitaxial, single-crystal Iron-Pnicitde Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ thin film near optimal doping (x=0.08) are measured under a localized and strong RF magnetic field, created by a near-field microwave microscope. Two reflection electrodynamic measurements, including linear and the third harmonic responses, are performed to understand the electromagnetic properties of Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$. Our measurement results show that Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ has have a wide superconducting transition width and may have a multi-gap nature. In addition, based on the $1/T^2$ dependence of the third harmonics signal at lower temperature, Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ shows the possibility of nodal behavior.

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Tamin Tai, Behnood G. Ghamsari, J. H. Kang, S. Lee, C. B. Eom, Steven M. Anlage. 2015-07-13. Localized High Frequency Electrodynamic Behavior of Optimally-doped Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ Single Crystal films. https://arxiv.org/abs/1507.03318

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