Full-Potential Study of the Magneto-Optical Kerr Effect for AuMnSb and AuMnSn

The magneto-optical Kerr effect (MOKE) for both Heusler type alloys (AuMnSb and AuMnSn) were studied using the full-potential linearized augmented plane-wave (FP-LAPW) method, based on the density functional theory implemented in the WIEN2k code. The differences with previous calculations on the Kerr spectra have been found explicitly. At proper Lorentzian such as δ = 0.4 eV, the calculated Kerr angle of AuMnSn reaches its maxima +0.3° near 0.6 eV and-0.5° at 5.2 eV, respectively while the MOKE spectra of AuMnSb exhibit less prominent Peaks (+0.5° at 0.3 eV, -1.9° at 0.9 eV, -1.0° at 2.4 eV and-2.0° at 5.3 eV). The results on the spectra in this work showed quite a lot differences with all previous all-electron calculations. It is concluded that the contribution from Sb (or Sn) site to the magneto-optical kerr effect is quite crucial in Heuslar alloys.