相关论文: ZnO:Co Diluted Magnetic Semiconductor or Hybrid Na…

Cobalt-doped ZnO (Co2+:ZnO) films were studied by magnetic circular dichroism (MCD) spectroscopy. A broad 300 K ferromagnetic MCD signal was observed between 1.4 and 4.0 eV after introducing shallow donor states by exposure of paramagnetic…

We consider the transport properties in an applied magnetic field of the spin S=1/2 Kondo model with ferromagnetic exchange coupling to electronic reservoirs, a description relevant for the strong coupling limit of underscreened spin S=1…

An emerging branch of electronics, the optospintronics, would be highly boosted if the control of magnetic order by light is implemented in magnetic semiconductors nanostructures being compatible with the actual technology. Here we show…

Structural and magnetic properties have been studied for polycrystalline Zn_{1-x}TM_xO, where TM (transition metal ions) = Mn, Fe, and Co. No bulk ferromagnetism was observed for single-phase materials, contrary to the existing theories.…

We have calculated the chemical trend of magnetic exchange parameters ($J_{dd}$, $N \alpha$, and $N \beta$) of Zn-based II-VI semiconductors ZnA (A=O, S, Se, and Te) doped with Co or Mn. We show that a proper treatment of electron…

The electronic structure and magnetic properties of La_{1-x}A_{x}MnO_3 are investigated. It is assumed that, at the outermost layer, the environment of the Mn ions does not have cubic symmetry. The e_g orbitals are split and the double…

The existence of semiconductors exhibiting long-range ferromagnetic ordering at room temperature still is controversial. One particularly important issue is the presence of secondary magnetic phases such as clusters, segregations, etc...…

Nd$_{2-x}$Ce$_x$CuO$_{4\pm\delta}$ (NCCO) epitaxial thin films have been deposited on (100) SrTiO$_3$ substrates by DC sputtering technique in different atmosphere. The as-grown samples show different dependence of the in-plane resistivity…

The results of ac and dc magnetization and heat capacity measurements on the oxides, Ca$_3$Co$_{1+x}$Mn$_{1-x}$O$_6$, forming in a K$_4$CdCl$_6$-derived rhombohedral quasi-one-dimensional crystal structure, are reported. As far as…

We report the magnetic properties in the Co- and Zn-doped spin-1/2 honeycomb-lattice compound In$_3$Cu$_2$VO$_9$. The magnetic susceptibility and specific heat experiments show no long-range ordering down to 2 K in In$_3$Cu$_2$VO$_9$. In…

The effect of Cu-doping at Mn-site on structural, magnetic and transport properties in electron-doped manganites La0.85Te0.15Mn1-xCuxO3 has been investigated. Based on the analysis of structural parameter variations, the valence state of…

Spectroscopic data demonstrate that impurity D/A levels in doped semiconductor nanostructures are energetically pinned, resulting in variations in D/A binding energies with increasing quantum confinement. Using magnetic circular dichroism…

We used a solid-state reaction method to prepare Sn$_{1-x}$Ni$_x$O$_2$ with $x$ = 0, 0.05, 0.1, 0.15 polycrystalline compounds. A rutile phase with tetragonal crystal structure was confirmed by X-ray diffraction. At room temperature, the…

We present SQUID susceptibility data on Zn and Ni substituted YBa_{2}Cu_{3}O_{6+x}. Cross-checks with NMR yield an unprecedented accuracy in the estimate of the magnetic susceptibility associated with the substituants, from the underdoped…

Mn doped semiconductors are extremely interesting systems due to their novel magnetic properties suitable for the spintronics applications. It has been shown recently by both theory and experiment that Mn doped GaN systems have a very high…

Our predictions, based on density-functional calculations, reveal that surface doping of ZnO nanowires with Bi leads to a linear-in-$k$ splitting of the conduction-band states, through spin-orbit interaction, due to the lowering of the…

Cubic spinel CoCr2O4 has attained recent attention due to its multiferroic properties. However, the Co site substitution effect on the structural and magnetic properties has rarely been studied in thin film form. In this work, the…

The nature of the often reported room temperature ferromagnetism in transition metal doped oxides is still a matter of huge debate. Herein we report on room temperature ferromagnetism in high quality Co-doped ZnO (Zn1-xCoxO) bulk samples…

Resistivity, Hall effect, magnetoresistance and DC magnetization were measured in Mn and Zn doped Ba$_{0.5}$K$_{0.5}$Fe$_{2}$As$_{2}$ samples. It is found that the Mn-doping can depress the superconducting transition temperature drastically…

Recent experiments in Pr(Nd)$_{0.5}$Ca$_{0.5}$MnO$_3$ thin films exhibited (multiple) reentrant charge ordering (CO) transitions with change of {\it temperature} T under fixed magnetic field H, which are in contrast to the results for the…