Magnetic Domain State and Anisotropy in Hematite ( <i>α</i> ‐Fe ₂ O ₃ ) From First‐Order Reversal Curve Diagrams

Hematite carries magnetic signals of interest in tectonic, paleoclimatic, paleomagnetic, and planetary studies. First-order reversal curve (FORC) diagrams have become an important tool for assessing the domain state of, magnetostatic interactions among, particles such We present here FORC diverse hematite samples, which provide a catalog comparison with other studies explain key features observed hematite. Ridge-type signatures typical uniaxial single-domain particle assemblages “kidney-shaped” signatures, combinations these responses, occur commonly natural synthetic Asymmetric that arise from triaxial basal plane anisotropy contribute to vertical spreading kidney-shaped distributions are intrinsic responses even magnetostatically noninteracting particles. The dominant distribution type sample (ridge, kidney-shaped, or mixture) depends on balance between uniaxial/triaxial switching. identified magnetization switching properties materials multiaxial anisotropy.