Charge Fluctuations in the NdO$_{1-x}$F$_{x}$BiS$_{2}$ Superconductors

Anushika Athauda; Yoshikazu Mizuguchi; Masanori Nagao; Joerg Neuefeind; Despina Louca

doi:10.7566/jpsj.86.124718

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arXiv · 1708.03957

Charge Fluctuations in the NdO$_{1-x}$F$_{x}$BiS$_{2}$ Superconductors

Anushika Athauda·Yoshikazu Mizuguchi·Masanori Nagao·Joerg Neuefeind·Despina Louca

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Abstract

The local atomic structure of superconducting NdO$_{1-x}$F$_{x}$BiS$_{2}$ ($x$=0.2 and 0.4) is investigated using neutron diffraction and the pair density function analysis technique. In the non-superconducting $x$=0.2 composition, ferrodistortive displacements of the pyramidal sulfur ions break the tetragonal symmetry and a superlattice structure emerges with peaks appearing at $h+k$ odd reflections superimposed on the even reflections of the $P4/nmm$ symmetry. In the superconducting $x$=0.4 composition, similar ferrodistortive displacements are observed but with different magnitudes coupled with in-plane Bi distortions. The distortions are indicative of charge fluctuations that may lead to charge localization and suppression of superconductivity.

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Anushika Athauda, Yoshikazu Mizuguchi, Masanori Nagao, Joerg Neuefeind, Despina Louca. 2017-08-13. Charge Fluctuations in the NdO$_{1-x}$F$_{x}$BiS$_{2}$ Superconductors. https://doi.org/10.7566/jpsj.86.124718

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