Intrinsic ferromagnetism in Hg1-xFexSe (0.00012 ≤ x ≤ 0.0013) diluted magnetic semiconductor bulk single crystals at room temperature: Role of hybridization of impurity electronic states

We investigate room-temperature structural properties and spontaneous magnetism in a series of Hg1-xFexSe (0.00012 ≤ x ≤ 0.0013) diluted magnetic semiconductor bulk single crystals grown by the Bridgman method. In order to elucidate the experimentally observed high-temperature magnetism in the studied systems, the dependencies of magnetization on magnetic field strength for the entire sample series were studied. Their detailed analysis revealed impurity contributions typical of ferromagnetic materials, which are described by magnetization curves with the parameters characterizing the spontaneous spin magnetism of the donor conduction electrons of the outer d-shells of the impurity atoms. According to the previously-developed theoretical concept, such a magnetic ordering mechanism stems from the direct exchange coupling of donor conduction electrons due to hybridization of impurity states, rather than from inter-impurity interactions. The results of optical emission spectroscopy and X-ray diffraction analysis confirmed the observed ferromagnetism to be intrinsic and linked directly to the d-electrons of iron impurity atoms

Hydrogen dynamics in the hexagonal Ho 2 Fe 17 H 4 and Y 2 Fe 17 H 4.2 : Inelastic and quasielastic neutron scattering studies

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Magnetic properties and electronic structure of CeFe<inf>2−x</inf>Mn<inf>x</inf> and CeFe<inf>2</inf>Mn<inf>x</inf> compounds

The effect of manganese alloying on the structure and magnetic properties of CeFe2 has been studied on two isostructural series: quasibinary CeFe2−xMnx and nonstoichiometric CeFe2Mnx alloys. The single-phase bcc MgCu2-type structure is formed at x≤0.5 in both systems. At x=0.5, the lattice parameter is increased by ∼0.3%. The Mn alloying leads to a nonmonotonic variation of magnetic moment and gradual decrease in the Curie temperature from 230 K to 150 K and 167 K for CeFe1.5Mn0.5 and CeFe2Mn0.5, respectively. For x≥0.3, the magnetization data indicate the formation of noncollinear magnetic structure. The binary CeFe2 and nonstoichiometric CeFe2Mn0.15 have been studied using Mössbauer effect and X-ray photoelectron spectroscopy. The Ce valence state remains unchanged upon the Mn alloying. The parameters of hyperfine interactions have been determined in paramagnetic state at room temperature and in magnetically ordered state at 78 K. The Mössbauer data revealed a difference in the quadrupole coupling constants of CeFe2 and CeFe2Mn0.15, which is associated with the difference in the local distortions of the lattice