Direct observation of the influence of the As-Fe-As angle on theTcof superconducting SmFeAsO1−xF

Gastón Garbarino

¹

,

Ruben Weht

²

,

Amadou Sow

³

et al.

Non-linear lattice response of Sm oxypnictides to hydrostatic pressure

“…Our structural data on the SmFeAsO 1-x F x compounds have been published elsewhere [17] and agree with other high pressure XRD measurements where lattice modifications were detected correlated with changes in T c [19]. tetrahedra.…”

Pressure induced lattice anomalies in pnictides

“…A non-monotonic pressure dependence of the Fe-As-Fe angles was reported in this compound indicating that pressure-induced lattice anomalies are present in this family of pnictide compounds, which correlate with modifications in the T c value [27]. Our hydrostatic pressure measurements on SmFeAsO 1 À x F x have also indicated small lattice anomalies and a non-linear dependence on pressure [19,20], further supporting the existence of such lattice anomalies in the superconducting compounds.…”

Superconductivity under pressure inRFeAsO1−xFx(Miyoshi1, Kojima2, Ogawa3 et al. 2013Phys. Rev. B

“…Pressure dependence of T c has been widely investigated by the ρ(T ) and M(T ) measurements for R = Sm, 15,17,26,28,30 Nd, 14 Pr, 30 and Ce, 16,22,24 and negative pressure coefficients of T c have been found in these studies. In particular, the investigations in the high-pressure range have been done by the ρ(T ) measurements adopting the onset temperature of resistive drop as T c for R = Sm and Nd, resulting in dT c /dP ∼ −3.0 K/GPa.…”

“…The pressure effect for RFeAsO 1−x F x has been investigated by many researchers through the measurements of electrical resistivity (ρ), [12][13][14][15][16][17][18][19][20][22][23][24][25][26] ac and dc magnetization, [27][28][29][30][31] x-ray diffraction, 19,26,32 NMR, 23,33 and others. 20,31 For LaFeAsO 1−x F x with x = 0.11, it has been suggested that T c increases with increasing pressure P and shows a maximum of 43 K at P ∼ 4 GPa through the ρ(T ) measurements by determining T c from the onset of resistive drop.…”