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arXiv · 1912.09384

Lattice dynamics in FeSe via inelastic x-ray scattering and first-principles calculations

Naoki Murai·Tatsuo Fukuda·Masamichi Nakajima·Mitsuaki Kawamura·Daisuke Ishikawa·Setsuko Tajima·Alfred Q. R. Baron
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Abstract

We report an inelastic x-ray scattering investigation of phonons in FeSe superconductor. Comparing the experimental phonon dispersion with density functional theory (DFT) calculations in the non-magnetic state, we found a significant disagreement between them. Improved overall agreement was obtained by allowing for spin-polarization in the DFT calculations, despite the absence of magnetic order in the experiment. This calculation gives a realistic approximation, at DFT level, of the disordered paramagnetic state of FeSe, in which strong spin fluctuations are present.

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Naoki Murai, Tatsuo Fukuda, Masamichi Nakajima, Mitsuaki Kawamura, Daisuke Ishikawa, Setsuko Tajima, Alfred Q. R. Baron. 2019-12-19. Lattice dynamics in FeSe via inelastic x-ray scattering and first-principles calculations. https://doi.org/10.1103/physrevb.101.035126

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