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Updated: Jan 8, 2026
Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
ANi2TeO6 (A = Sr, Ca, and Cd): Canted Antiferromagnets Featuring a CaFe2O4-Type Superstructure with Double 2:1
Siqi Ma1, Shunjie Tang1, Zien Cheng1
1College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 401331, China.
None:
The intriguing magnetism of CaFe2O4-type oxides arises from the coexistence of a honeycomb-like network and one-dimensional zigzag ladders, providing a platform for unconventional magnetic states. In this work, we strategically introduced long-range cationic ordering into this framework to tune competing magnetic interactions. Here, a series of ordered CaFe2O4-type oxides A□1/2Ni2TeO6 (ANi2TeO6, A = Sr, Ca, or Cd; □ = A-site vacancy) were rationally designed, synthesized, and structurally characterized. ANi2TeO6 crystallizes in Pnma with a 3-fold superstructure originating from the 2:1 ordering of Ni2+ and Te6+ cations along two symmetry-independent zigzag ladders. This ordering further triggers a 2:1 periodic arrangement of A2+ cations and vacancies along the hexagonal tunnel, minimizing the cation-cation electrostatic repulsion. Low-temperature NPD analysis reveals alternating ferromagnetic and antiferromagnetic coupling within each ladder, with Ni22+ spin moments adopting an up-up-down-down configuration along the b-axis, whereas Ni12+ spins are canted within the ab-plane, producing a net magnetic moment along the a-axis and thus a ferromagnetic-like magnetic transition. Adjacent ladders couple antiferromagnetically, yielding a magnetic structure consistent with Pnm'a'. This work establishes a strategy of cationic ordering to expand the structural chemistry of CaFe2O4-type oxides, thereby offering new opportunities for the study of competing magnetic interactions and the development of novel magnetic materials.
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