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arXiv · 1008.3176

Far-Infrared Conductivity Measurements of Pair Breaking in Superconducting Nb$_{0.5}$Ti$_{0.5}$N Thin Films Induced by an External Magnetic Field

Xiaoxiang Xi·J. Hwang·C. Martin·D. B. Tanner·G. L. Carr
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Abstract

We report the complex optical conductivity of a superconducting thin-film of Nb$_{0.5}$Ti$_{0.5}$N in an external magnetic field. The field was applied parallel to the film surface and the conductivity extracted from far-infrared transmission and reflection measurements. The real part shows the superconducting gap, which we observe to be suppressed by the applied magnetic field. We compare our results with the pair-breaking theory of Abrikosov and Gor'kov and confirm directly the theory's validity for the optical conductivity.

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Xiaoxiang Xi, J. Hwang, C. Martin, D. B. Tanner, G. L. Carr. 2010-08-18. Far-Infrared Conductivity Measurements of Pair Breaking in Superconducting Nb$_{0.5}$Ti$_{0.5}$N Thin Films Induced by an External Magnetic Field. https://doi.org/10.1103/physrevlett.105.257006

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