相关论文: Aggregation and magnetism of Cr, Mn, and Fe cation…

The magnetic coupling between doped Mn atoms in clusters as well as crystals of GaN has been studied from first principles using molecular orbital theory for clusters and linearized muffin tin orbitals-tight binding formulation (LMTO-TB)…

While isovalent doping of GaAs (e.g. by In) leads to a repulsion between the solute atoms, two Cr, Mn, or Fe atoms in GaAs are found to have lower energy than the well-separated pair, and hence attract each other. The strong bonding…

Otherwise antiferromagnetic chromium is shown to couple ferromagnetically when doped into GaN irrespective of whether the host is a crystal or a cluster. The results on the doped clusters and crystals are obtained from density functional…

We investigate the electronic and magnetic properties of (Ga,Mn)N nanocrystals using the density functional theory. We study both wurtzite and zinc-blende structures doped with one or two substitutional Mn impurities. For a single Mn dopant…

The structural, electronic and magnetic properties of small ${\rm Fe}_m {\rm Rh}_n$ clusters having $N = m+n \leq 8$ atoms are studied in the framework of a generalized-gradient approximation to density-functional theory. The correlation…

While most calculations on the properties of the ferromagnetic semiconductor GaAs:Mn have focussed on isolated Mn substituting the Ga site (Mn$_{Ga}$), we investigate here whether alternate lattice sites are favored and what the magnetic…

Mn-doped wurtzite GaN epilayers have been grown by nitrogen plasma-assisted molecular beam epitaxy. Correlated SIMS, structural and magnetic measurements show that the incorporation of Mn strongly depends on the conditions of the growth.…

A ferromagnetic coupling between localized Mn spins was predicted in a series of \textit{ab initio} and tight binding calculations and experimentally verified for the dilute magnetic semiconductor Ga$_{1-x}$Mn$_x$N. In the limit of small Mn…

The structural, electronic and magnetic properties of small ${\rm Fe}_m {\rm Rh}_n$ clusters having $N = m+n \leq 8$ atoms are studied in the framework of a generalized-gradient approximation to density-functional theory. For $N = m+n \leq…

In this letter, the authors present a study of the energetics and magnetic interactions in Fe doped ZnO clusters by ab-initio density functional calculations. The results indicate that defects under suitable conditions can induce…

Zn1-xRxO (R = Li, Mg, Cr, Mn, Fe and Cd) were obtained by using co-precipitation synthesis technique with constant weight percent of 3% from R ions. The phase composition, crystal structure, morphology, Density Functional Theory (DFT), and,…

The effect of Mg codoping and its deposition mode on the Fe distribution in (Ga,Fe)N layers grown by metalorganic vapor phase epitaxy is investigated. Both homogeneously- and digitally-Mg codoped samples are considered and contrasted to the…

We present a detailed study of the magnetic properties of unique cluster assembled solids namely Mn doped Ge46 and Ba8Ge46 clathrates using density functional theory. We find that ferromagnetic (FM) ground states may be realized in both the…

Geometry, electronic structure, and magnetic properties of TMNan (TM=Cr-Ni; n = 4-7) clusters are studied within a gradient corrected density functional theory (DFT) framework. Two complementary approaches, the first adapted to all-electron…

Ni-Mn-Ga is interesting as a prototype of a magnetic shape-memory alloy showing large magnetic field induced strains. We present here results for the magnetic ordering of Mn-rich Ni-Mn-Ga alloys based on both experiments and theory.…

Enhancement of magnetism of Fe that occurs by alloying with Cr or V is discussed on the basis of first-principles electronic structure calculation. The d states of Fe next to Cr(V) are pushed down to the lower energy side compared to those…

The control on the distribution of magnetic ions into a semiconducting host is crucial for the functionality of magnetically doped semiconductors. Through a structural analysis at the nanoscale, we give experimental evidence that the…

Ferromagnetic couplings in spin clusters are shown to be strongly enhanced compared to those for an ordered impurity arrangement, even for the same spin separation and hole doping. The consequent energy-enhancement of the cluster-localized…

Using spin density functional theory we have carried out a comparative study of chemical bonding and magnetism in Fe_4N, Fe_3N and Fe_2N. All of these compounds form close packed Fe lattices, while N occupies octahedral interstitial…

The percentage of substitutional doping of magnetic atoms (Mn) in group-IV-based dilute magnetic semiconductors (DMS) can be increased by co-doping with another conventional electronic dopant (e-dopant) [Zhu et al., Phys. Rev. Lett. 100,…