6533b7ddfe1ef96bd1275140

RESEARCH PRODUCT

Localized magnetic moments in the Heusler alloy Rh2MnGe

H. J. ElmersLubna BasitM. KallmayerStanislav ChadovP. KlaerClaudia FelserJ. Thöne

subject

X-ray absorption spectroscopyAcoustics and UltrasonicsCondensed matter physicsAbsorption spectroscopyMagnetic momentMagnetic circular dichroismHeisenberg modelChemistryCondensed Matter PhysicsSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsCondensed Matter::Materials ScienceMagnetizationFerromagnetismCondensed Matter::Strongly Correlated ElectronsLocal-density approximation

description

X-ray magnetic circular dichroism (XMCD) of core-level absorption (x-ray absorption spectroscopy, XAS) spectra in the soft x-ray region has been measured for the ferromagnetic Heusler alloy Rh2MnGe at the Rh M3,2 and Mn L3,2 edges. The ratio of Rh and Mn spin moments amounts to 0.05 which is smaller than the ratio of 0.1 determined by a local density approximation electronic band structure calculation. We have found that the orbital moments of the Rh 4d and Mn 3d states are very small. The observed Rh 2p XAS spectrum can be understood on the basis of the Rh 3d partial density of unoccupied states as is typical for metals. The observed features of the Mn 2p XAS and XMCD spectra are dominated by final state multiplets as is typical for oxides. The comparison of experimental and ab initio calculated XAS/XMCD spectra reveals a strong narrowing of the Mn 3d bands, indicating strongly localized Mn moments. The magnetic moments are considerably more localized for Rh2MnGe in comparison with the isoelectronic compound Co2MnGe. In spite of the strong localization of the Mn moment, the temperature dependences of sublattice magnetization are equal for the Mn and Rh sublattices in contrast to the prediction by a Heisenberg model. This might be attributed to the remaining itinerant character of the Rh moment.

https://doi.org/10.1088/0022-3727/42/8/084001