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arXiv · 1008.2019

Local quasiparticle density of states of superconducting SmFeAsO$1-x$F$x$ single crystals: Evidence for spin-mediated pairing

Y. Fasano·I. Maggio-Aprile·N. D. Zhigadlo·S. Katrych·J. Karpinski·Ø. Fischer
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Abstract

We probe the local quasiparticles density-of-states in micron-sized SmFeAsO$_{1-x}$F$_{x}$ single-crystals by means of Scanning Tunnelling Spectroscopy. Spectral features resemble those of cuprates, particularly a dip-hump-like structure developed at energies larger than the gap that can be ascribed to the coupling of quasiparticles to a collective mode, quite likely a resonant spin mode. The energy of the collective mode revealed in our study decreases when the pairing strength increases. Our findings support spin-fluctuation-mediated pairing in pnictides.

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Y. Fasano, I. Maggio-Aprile, N. D. Zhigadlo, S. Katrych, J. Karpinski, Ø. Fischer. 2010-08-11. Local quasiparticle density of states of superconducting SmFeAsO$1-x$F$x$ single crystals: Evidence for spin-mediated pairing. https://doi.org/10.1103/physrevlett.105.167005

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