Direct observation of the influence of the As-Fe-As angle on the Tc of superconducting SmFeAsO$_{1-x}$F$_{x}$

G. Garbarino; R. Weht; A. Sow; A. Sulpice; P. Toulemonde; M. Álvarez-Murga; P. Strobel; P. Bouvier; M. Mezouar; M. Núñez-Regueiro

doi:10.1103/physrevb.84.024510

arXiv · 1106.1361

Direct observation of the influence of the As-Fe-As angle on the Tc of superconducting SmFeAsO$_{1-x}$F$_{x}$

G. Garbarino·R. Weht·A. Sow·A. Sulpice·P. Toulemonde·M. Álvarez-Murga·P. Strobel·P. Bouvier·M. Mezouar·M. Núñez-Regueiro

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Abstract

The electrical resistivity, crystalline structure and electronic properties calculated from the experimentally measured atomic positions of the compound SmFeAsO$_{0.81}$F$_{0.19}$ have been studied up to pressures ~20GPa. The correlation between the pressure dependence of the superconducting transition temperature (Tc) and crystallographic parameters on the same sample shows clearly that a regular FeAs$_{4}$ tetrahedron maximizes Tc, through optimization of carrier transfer to the FeAs planes as indicated by the evolution of the electronic band structures.

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G. Garbarino, R. Weht, A. Sow, A. Sulpice, P. Toulemonde, M. Álvarez-Murga, P. Strobel, P. Bouvier, M. Mezouar, M. Núñez-Regueiro. 2011-06-07. Direct observation of the influence of the As-Fe-As angle on the Tc of superconducting SmFeAsO$_{1-x}$F$_{x}$. https://doi.org/10.1103/physrevb.84.024510

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