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arXiv · 1701.03258

Interplay of iron and rare-earth magnetic order in rare-earth iron pnictide superconductors under magnetic field

Lei-Lei Yang·Da-Yong Liu·Dong-Meng Chen·Liang-Jian Zou
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Abstract

The magnetic properties of iron pnictide superconductors with magnetic rare-earth ions under strong magnetic field are investigated based on the cluster self-consistent field method. Starting from an effective Heisenberg model, we present the evolution of magnetic structures on magnetic field in RFeAsO (R=Ce, Pr, Nd, Sm, Gd and Tb) and RFe2As2 (R=Eu) compounds. It is found that spin-flop transition occurs in both rare-earth and iron layers under magnetic field, in good agreement with the experimental results. The interplay between rare-earth and iron spins plays a key role in the magnetic-field-driven magnetic phase transition, which suggests that the rare-earth layers can modulate the magnetic behaviors of iron layers. In addition, the factors that affect the critical magnetic field for spin-flop transition are also discussed.

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Lei-Lei Yang, Da-Yong Liu, Dong-Meng Chen, Liang-Jian Zou. 2017-01-12. Interplay of iron and rare-earth magnetic order in rare-earth iron pnictide superconductors under magnetic field. https://doi.org/10.1088/1674-1056/25/2/027401

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