From magnetic circular dichroism measurements of the Heusler alloy NiMnSb, in combination with other techniques, we show that a dramatic increase in the Mn and Ni moments occurs below a "crossover" transition temperature of about 80-100 K. This phase transition is well below the Curie temperature of NiMnSb (∼730 K). While the spin polarization near the Fermi level, from spin-polarized inverse photoemission, remains very high for k=0, it is unlikely that NiMnSb is a half-metallic ferromagnet near room temperature.
Publication Source (Journal or Book title)
Physical Review B - Condensed Matter and Materials Physics
Borca, C., Komesu, T., Jeong, H., Dowben, P., Ristoiu, D., Hordequin, C., Nozières, J., Pierre, J., Stadler, S., & Idzerda, Y. (2001). Evidence for temperature dependent moments ordering in ferromagnetic NiMnSb(100). Physical Review B - Condensed Matter and Materials Physics, 64 (5), 0524091-0524094. https://doi.org/10.1103/PhysRevB.64.052409