Spin-flop transition driven by competing magnetoelastic anisotropy terms in a spin-spiral antiferromagnet

Article

关键词: ANOMALOUS THERMAL-EXPANSION;    RARE-EARTH-METALS;    X-RAY SCATTERING;    MAGNETIC-STRUCTURES;    HOLMIUM;    MAGNETOSTRICTION;    DYSPROSIUM;    SURFACE;    SUPERLATTICES;    REORIENTATION;   

DOI  :  10.1103/PhysRevB.91.214428

来源: SCIE

【 摘 要 】

Holmium, the archetypical system for spin-spiral antiferromagnetism, undergoes an in-plane spin-flop transition earlier attributed to competing symmetry-breaking and fully symmetric magnetoelastic anisotropy terms [Phys. Rev. Lett. 94, 227204 (2005)], which underlines the emergence of sixfold magnetoelastic constants in heavy rare earth metals, as otherwise later studies suggested. A model that encompasses magnetoelastic contributions to the in-plane sixfold magnetic anisotropy is laid out to elucidate the mechanism behind the spin-flop transition. The model, which is tested in a Ho-based superlattice, shows that the interplay between competing fully symmetric alpha-magnetoelastic and symmetry-breaking gamma-magnetoelastic anisotropy terms triggers the spin reorientation. This also unveils the dominant role played by the sixfold exchange magnetostriction constant, where D-alpha 2(66) similar or equal to 0.32 GPa against its crystal-field counterpart M-alpha 2(66) similar or equal to -0.2 GPa, in contrast to the crystal-field origin of the symmetry-breaking magnetostriction in rare earth metals.

【 授权许可】

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