English
Related papers

Related papers: Electronic structure and magnetism in disordered b…

200 papers

We have studied the local electronic structure of LaMn0.5Co0.5O3 using soft-x-ray absorption spectroscopy at the Co-L_3,2 and Mn-L_3,2 edges. We found a high-spin Co^{2+}--Mn^{4+} valence state for samples with the optimal Curie…

Strongly Correlated Electrons · Physics 2008-03-18 T. Burnus , Z. Hu , H. H. Hsieh , V. L. J. Joly , P. A. Joy , M. W. Haverkort , Hua Wu , A. Tanaka , H. -J. Lin , C. T. Chen , L. H. Tjeng

Experiments showed that solute Mn in bcc iron is in antiferromagnetic (AFM) coupling with iron neighbours below 2 at.% Mn, but is in ferromagnetic (FM) coupling at higher concentrations. Surprisingly, although Mn is an important alloying…

Co-rich Co$_{1-x}$Mn$_x$ alloys have hcp or fcc disordered phases and those ferromagnetic orderings are significantly deteriorated with increasing Mn concentration $x$ in bulk. On the other hand, those metastable bcc phases show properties…

Electronic structure calculations of the Verwey ground state of magnetite, Fe3O4, using density functional theory with treatment of on-site Coulomb interactions (DFT+U scheme) are reported. These calculations use the recently-published…

Strongly Correlated Electrons · Physics 2013-01-16 Mark Senn , Ingo Loa , Jon P. Wright , J. Paul Attfield

Recent experimental studies on Fe substituted spinel CoCr$_{2}$O$_{4}$ have discovered multiple functional properties in the system such as temperature and composition dependent magnetic compensation, tunable exchange bias and…

Materials Science · Physics 2018-08-29 Debashish Das , Subhradip Ghosh

Low-temperature measurements of the magnetocrystalline anisotropy energy $K$ in (Fe$_{1-x}$Co$_{x}$)$_{2}$B alloys are reported, and the origin of this anisotropy is elucidated using a first-principles electronic structure analysis. The…

Lattice parameter, bulk modulus, formation energy and magnetism equilibrium structure in all-d transition metals $Ni_2XMn$ (X=Co,Cr,Fe) for Full and Inverse Heusler structure are studied by first-principles calculations. Tetragonal…

Materials Science · Physics 2023-02-14 A. Alés

We explain a profound complexity of magnetic interactions of some technologically relevant gadolinium intermetallics using an ab-initio electronic structure theory which includes disordered local moments and strong $f$-electron…

We study the electronic structure and the magnetic correlations of cyanocobalamin ($C_{63}H_{88}CoN_{14}O_{14}P$) by using the framework of the multi-orbital single-impurity Haldane-Anderson model of a transition metal impurity in a…

Strongly Correlated Electrons · Physics 2016-05-31 Selma Mayda , Zafer Kandemir , Nejat Bulut

Using first-principles calculations based on density functional theory, we probe the electronic and magnetic properties of X$_{2}$PtGa (X being Cr, Mn, Fe, Co) Heusler alloys. Our calculations predict that all these systems possess inverse…

Materials Science · Physics 2016-11-23 Tufan Roy , Aparna Chakrabarti

The structure and magnetic properties of nanocrystalline PrCo$_3$ obtained from high energy milling technique are investigated by X-ray diffraction, Curie temperature determination and magnetic properties measurements are reported. The…

Materials Science · Physics 2015-05-28 K. Younsi , V. Russier , L. Bessais , J. -C. Crivello

The magnetic properties of Mn, Co and Ni substituted Fe4N are calculated from first principles theory. It is found that the generalized gradient approximation reproduces with good accuracy the magnetic moment and equilibrium volume for the…

Materials Science · Physics 2014-08-07 Patrizia Monachesi , Torbjörn Björkman , Thomas Gasche , Olle Eriksson

Exchange couplings are fundamental to our understanding of many physical phenomena in condensed matter physics and material science. Model systems provide a controlled environment to investigate such phenomena, effectively. In this study,…

Materials Science · Physics 2024-11-26 Mahnaz Rezaei , Jahanfar Abouie , Fariba Nazari

The infinite-dimensional Hubbard model is studied by means of a modified perturbation theory. The approach reduces to the iterative perturbation theory for weak coupling. It is exact in the atomic limit and correctly reproduces the…

Strongly Correlated Electrons · Physics 2009-10-30 T. Wegner , M. Potthoff , W. Nolting

We use bulk magnetic susceptibility, electronic specific heat, and neutron scattering to study structural and magnetic phase transitions in Fe$_{1+y}$Se% $_x$Te$_{1-x}$. Fe$_{1.068}$Te exhibits a first order phase transition near 67 K with…

This study deals with cubic crystals where the contents of the simple cubic unit cells are close to n$\times$n$\times$n-bcc sublattices ($n$ = 2: diamond- and zinc-blende type, $n$ = 3: $\gamma$-brasses). First-principle results on the…

Materials Science · Physics 2023-03-23 Heinrich Solbrig

Using the experimentally measured temperature and doping dependent structural parameters on Ru doped BaFe$_2$As$_2$, orbital-dependent reconstruction of the electronic structure across the magnetostructural transition is found, through…

Superconductivity · Physics 2015-06-22 Smritijit Sen , Haranath Ghosh , A. K. Sinha , A. Bharathi

We present a combined theoretical and experimental study of two quaternary Heusler alloys CoFeCrGe (CFCG) and CoMnCrAl (CMCA), promising candidates for spintronics applications. Magnetization measurement shows the saturation magnetization…

Materials Science · Physics 2016-01-20 Enamullah , Y. Venkateswara , Sachin Gupta , Manoj Raama Varma , Prashant Singh , K G Suresh , Aftab Alam

Magnetic refrigeration based on the magnetocaloric effect (MCE) of materials is a potential technique that has prominet advantages over the currently used gas compression-expansion technique in the sense of its high efficiency and…

Materials Science · Physics 2023-10-18 B. G. Shen , J. R. Sun , F. X. Hu , H. W. Zhang , Z. H. Cheng

Variant approaches, either based on the Fermi surface nesting or started from the proximity to a Mott-insulator, were proposed to elucidate the physics in iron pnictides, but no consensus has been reached. A fundamental problem concerns the…

Superconductivity · Physics 2011-03-01 H. Q. Yuan , L. Jiao , F. F. Balakirev , J. Singleton , C. Setty , J. P. Hu , T. Shang , L. J. Li , G. H. Cao , Z. A. Xu , B. Shen , H. H. Wen