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Ferroelectric phase transition in multiferroic Ge1-x Mn x Te driven by local lattice distortions.

ABSTRACT: The evolution of local ferroelectric lattice distortions in multiferroic Ge1-x Mn x Te is studied by x-ray diffraction, x-ray absorption spectroscopy and density functional theory. We show that the anion/cation displacements smoothly decrease with increasing Mn content, thereby reducing the ferroelectric transition from 700 to 100 K at x = 0.5, where the ferromagnetic Curie temperature reaches its maximum. First principles calculations explain this quenching by different local bond contributions of the Mn 3d shell compared to the Ge 4s shell in excellent quantitative agreement with the experiments.

SUBMITTER: Kriegner D

PROVIDER: S-EPMC5404721 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Ferroelectric phase transition in multiferroic Ge1-x Mn x Te driven by local lattice distortions.

Kriegner Dominik D Furthmüller Jürgen J Kirchschlager Raimund R Endres Jan J Horak Lukas L Cejpek Petr P Reichlova Helena H Marti Xavier X Primetzhofer Daniel D Ney Andreas A Bauer Günther G Bechstedt Friedhelm F Holy Vaclav V Springholz Gunther G

Physical review. B 20160819 5

The evolution of local ferroelectric lattice distortions in multiferroic Ge1-x Mn x Te is studied by x-ray diffraction, x-ray absorption spectroscopy and density functional theory. We show that the anion/cation displacements smoothly decrease with increasing Mn content, thereby reducing the ferroelectric transition from 700 to 100 K at x = 0.5, where the ferromagnetic Curie temperature reaches its maximum. First principles calculations explain this quen ...[more]

PMID: 28459114

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