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arXiv · 0908.1167

Suppression of the Superconducting Transition in RFeAsO1-xFx for R = Tb, Dy, Ho

J. A. Rodgers·G. B. S. Penny·A. Marcinkova·J. W. G. Bos·D. A. Sokolov·A. Kusmartseva·A. D. Huxley·J. P. Attfield
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Abstract

A suppression of superconductivity in the late rare earth RFeAsO1-xFx materials is reported. The maximum critical temperature (Tc) decreases from 51 K for R = Tb to 36 K for HoFeAsO0.9F0.1, which has been synthesised under 10 GPa pressure. This suppression is driven by a decrease in the Fe-As-Fe angle below an optimimum value of 110.6 degrees, as the angle decreases linearly with unit cell volume (V) across the RFeAsO1-xFx series. A crossover in electronic structure around this optimum geometry is evidenced by a change in sign of the compositional dTc/dV, from negative values for previously reported large R materials to positive for HoFeAsO0.9F0.1.

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J. A. Rodgers, G. B. S. Penny, A. Marcinkova, J. W. G. Bos, D. A. Sokolov, A. Kusmartseva, A. D. Huxley, J. P. Attfield. 2009-08-08. Suppression of the Superconducting Transition in RFeAsO1-xFx for R = Tb, Dy, Ho. https://arxiv.org/abs/0908.1167

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