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arXiv · 1412.3995

Structure, magnetic order and excitations in the 245 family of Fe-based superconductors

Wei Bao
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Abstract

Elastic neutron scattering simultaneously probes both the crystal structure and magnetic order in a material. Inelastic neutron scattering measures phonons and magnetic excitations. Here, we review the average composition, crystal structure and magnetic order in the 245 family of Fe-based superconductors and in related insulating compounds from neutron diffraction works. A three-dimensional phase-diagram summarizes various structural, magnetic and electronic properties as a function of the sample composition. A high pressure phase diagram for the superconductor is also provided. Magnetic excitations and the theoretic Heisenberg Hamiltonian are provided for the superconductor. Issues for future works are discussed.

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Wei Bao. 2014-12-12. Structure, magnetic order and excitations in the 245 family of Fe-based superconductors. https://doi.org/10.1088/0953-8984%2F27%2F2%2F023201

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