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arXiv · 1001.5154

Static and Dynamical Susceptibility of LaO1-xFxFeAs

M. Monni·F. Bernardini·G. Profeta·A. Sanna·S. Sharma·J. K. Dewhurst·C. Bersier·A. Continenza·E. K. U. Gross·S. Massidda
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Abstract

The mechanism of superconductivity and magnetism and their possible interplay have recently been under debate in pnictides. A likely pairing mechanism includes an important role of spin fluctuations and can be expressed in terms of the magnetic susceptibility chi. The latter is therefore a key quantity in the determination of both the magnetic properties of the system in the normal state, and of the contribution of spin fluctuations to the pairing potential. A basic ingredient to obtain chi is the independent-electron susceptibility chi0. Using LaO1-xFxFeAs as a prototype material, in this report we present a detailed ab-initio study of chi0(q,omega), as a function of doping and of the internal atomic positions. The resulting static chi0(q,0) is consistent with both the observed M-point related magnetic stripe phase in the parent compound, and with the existence of incommensurate magnetic structures predicted by ab-initio calculations upon doping.

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M. Monni, F. Bernardini, G. Profeta, A. Sanna, S. Sharma, J. K. Dewhurst, C. Bersier, A. Continenza, E. K. U. Gross, S. Massidda. 2010-01-28. Static and Dynamical Susceptibility of LaO1-xFxFeAs. https://doi.org/10.1103/physrevb.81.104503

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