Related papers: Evidence for impurity-induced frustration in La2Cu…
Effects of nonmagnetic impurity doping on an AF spin-1/2 Heisenberg ladder system are studied by the QMC method. A single nonmagnetic impurity induces a localized spin-1/2 moment accompanied by "static" and enhanced AF correlations around…
Spin fluctuations and the local spin susceptibility in isovalently Zn-substituted La$_{2-x}$Sr$_{x}$Cu$_{1-y}$Zn$_y$O$_4$ ($x=0.25$, $y\approx0.01$) are measured via inelastic neutron scattering techniques. As Zn$^{2+}$ is substituted onto…
We report static and dynamic properties of the antiferromagnetic compound Zn$_{2}$(VO)(PO$_{4}$)$_{2}$, and the consequences of non-magnetic Ti$^{4+}$ doping at the V$^{4+}$ site. $^{31}$P nuclear magnetic resonance (NMR) spectra and…
We have investigated the magnetism and the superconductivity of an electron-doped Pr$_{1-x}$LaCe$_{x}$CuO$_{4}$ (PLCCO) using single crystal and powder samples by means of zero-field muon spin rotation/relaxation (ZF-$\mu$SR) and magnetic…
We studied structural and magnetic properties of a series of insulating double perovskite compounds, La$_{2-x}$Sr$_{x}$CuRuO$_{6}$ (0 $\le$ x $\le$ 1), representing doping via \textit{A}-site substitution. The end members…
Versatile features of impurity doping effects on perovskite manganites, $R_{0.6}$Sr$_{0.4}$MnO$_{3}$, have been investigated with varying the doing species as well as the $R$-dependent one-electron bandwidth. In ferromagnetic-metallic…
We have studied the influence of intrinsic and extrinsic defects in the magnetic and electrical transport properties of Co-doped ZnO thin films. X ray absorption measurements show that Co substitute Zn in the ZnO structure and it is in the…
We report comprehensive studies of the crystallographic,magnetic, and thermal properties of a spinel-type magnetically frustrated compound, CoAl2O4, and a magnetically diluted system,Co1-xZnxAl2O4. These studies revealed the effects of…
We have studied the interlayer coupling in the antiferromagnetic (AF) phase of Sr and Zn doped La2CuO4 by analyzing the spin flip transition in the magnetization curves. We find that the interlayer coupling strongly depends on the mobility…
Impurity effects on the triangular antiferromagnets Ni$_{1-x}M_x$Ga$_2$S$_4$ ($M=$ Mn, Fe, Co and Zn) are studied. The 2D frozen spin-disordered state of NiGa$_2$S$_4$ is stable against the substitution of Zn$^{2+}$ ($S=0$) and Heisenberg…
An inelastic neutron scattering study was performed on a Zn-substituted spin-1/2 Heisenberg 2-leg ladder compound Sr(Cu1-xZnx)2O3 (x < 0.04) to investigate nonmagnetic impurity effects on the quantum spin system with a large spin gap of…
Spinel ferrite Cu1-xZnxFe2O4 nanofibers over a compositional range 0 < x < 1 were prepared by electrospinning combined with sol-gel method. The influence of Zn2+ ions substitution on morphology, structure, and magnetic properties of copper…
Muon-spin-relaxation measurements have been performed for the partially Zn-substituted La_2-x_Sr_x_Cu_1-y_Zn_y_O_4_ with y=0-0.10 in the overdoped regime up to x=0.30. In the 3 % Zn-substituted samples up to x=0.27, exponential-like…
We present the results of a muon-spin relaxation study of GeNi2O4. We provide further clarification of the two transitions to the antiferromagnetic state and measure the magnetic field dependence of the heat capacity up to 14 T. Both…
Effects of the Zn- and Ni-substitution on the Cu-spin dynamics in the electron-doped Pr0.86LaCe0.14Cu1-y(Zn,Ni)yO4+a-d with y = 0, 0.01, 0.02, 0.05 and different values of the reduced oxygen content d have been studied using zero-field…
We report the characterisation of natural samples of the cubic pyrite mineral MnS2 using very high resolution synchrotron X-ray diffraction techniques. At low temperatures we find a new low temperature polymorph, which results from coupling…
The influence of zinc doping and strain related effects on the normal state transport properties(the resistivity, the Hall angle and the orbital magneto- resistance(OMR) is studied in a series of La1.85Sr0.15Cu(1-y)Zn(y)O4 films with values…
A weakening of superconductivity upon substitution of Cu by Zn (0.5~1 %) is observed in a high-T_c cuprate, Ca_{2-x}Na_xCuO2Cl2, near the hole concentration of 1/8 per Cu. The superconducting transition temperature and its volume fraction,…
The effect of isoelectronic substitutions on the microscopic properties of LaFe1-xRuxAsO, for 0< x< 0.8, has been investigated by means of muSR and 139La NMR. It was found that Ru substitution causes a progressive reduction of the N\`eel…
We present a 31P NMR study of the coupled spin 1/2 ladder compound BiCu2PO6. In the pure material, intrinsic susceptibility and dynamics show a spin gap of about . Substitution of non magnetic Zn or magnetic Ni impurity at Cu site induces a…