相关论文: Doping Effects on the two-dimensional Spin Dimer C…
We calculate the spin correlation function and the magnetic longitudinal and transverse susceptibilities of a two-dimensional antiferromagnet doped with a small concentration of holes, in the t-J model. We find that the motion of holes…
The structural and magnetic properties of polycrystalline YMn1-xMxO3 (M = Ti, Fe, Ga; x = 0, 0.1) have been studied by neutron powder diffraction and magnetic measurements to probe the effect of Mn site doping on the frustration behavior…
On the basis of Quantum Monte Carlo simulations of the two-dimensional Hubbard model which cover the doping range from the under- to the over-doped regime, we find that the single-particle spectral weight $A (\vec k,\omega)$ qualitatively…
We investigate the imaginary part of the wave vector dependent dynamic spin susceptibility in Sr$_2$(Ru$_{0.99}$Ti$_{0.01}$)O$_4$ as a function of temperature using neutron scattering. At T=5 K, two-dimensional incommensurate (IC) magnetic…
$Na_xCoO_2$ has a fascinating and complex magnetic phase diagram that can be further manipulated by doping. Here, we investigated the effect of electron doping on the magnetic coupling among $Co^{4+}$ ions in $Na_xCoO_2$ using density…
We investigated the magnetic properties of (La$_{1-x}$Ba$_{x}$)(Zn$_{1-x}$Mn$_{x}$)AsO with $x$ varying from 0.005 to 0.05 at an external magnetic field of 1000 Oe. For doping levels of $x$ $\leq$ 0.01, the system remains paramagnetic down…
We report a pressure study on electron doped SrFe$_{2-x}$Co$_x$As$_2$ by electrical-resistivity ($\rho$) and magnetic-susceptibility ($\chi$) experiments. Application of either external pressure or Co substitution rapidly suppresses the…
The doping effect of Sr and transition metals Mn, Fe, Co into the direct-gap semiconductor LaZnAsO has been investigated. Our results indicate that the single phase ZrCuSiAs-type tetragonal crystal structure is preserved in…
To investigate the relationship between the pseudogap and superconductivity, we measured both the in-plane ($\rho_{ab}$) and out-of-plane ($\rho_c$) resistivity for oxygen-controlled Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+\delta}$ single crystals…
We have synthesized the polycrystalline samples of Eu1-xKxFe2As2 (x = 0-1) and carried out systematic characterization using x-ray diffraction, ac & dc magnetic susceptibility, and electrical resistivity measurements. We have seen a clear…
The evolution of the superconducting properties of the carbon-doped MgB2 superconductors, MgB(2-x)Cx (x= 0.02, 0.04, 0.06) have been investigated by the transverse-field muon spin rotation (TF-muSR) technique. The low-temperature…
We report measurements of the Gaussian contribution, T_{2G}, to the plane ^{63}Cu nuclear spin--spin relaxation time in the YBa_2Cu_3O_7 and YBa_2Cu_4O_8 blocks of normal and superconducting Y_2Ba_4Cu_7O_{15}. The data confirm our previous…
We present a study of the magnetic susceptibility in carefully detwinned La_{2-x}Sr_{x}CuO_4 single crystals in the lightly-doped region (x=0-0.03), which demonstrates a remarkable in-plane anisotropy of the spin system. This anisotropy is…
We have performed extensive zero field muSR experiments on pure YBa2Cu3O6+y and diluted Y-rare-earth substituted Y0.92Eu0.08Ba2Cu3O6+y and Y0.925Nd0.075Ba2Cu3O6+y at light hole-doping. A common magnetic behavior is detected for all the…
We report on the ab-plane reflectance of the high temperature superconductor Bi2Sr2CaCu2O8+d (Bi-2212). Samples spanning the doping range from under doped with Tc = 67 K(UD), to optimally doped with Tc = 96 K (OPT), to over doped with Tc =…
This study investigates the effects of Sb, Ge, and Ga doping in AlFe$_2$B$_2$ on magnetic and magneto-caloric properties. Samples of AlFe$_2$B$_2$ and AlFe$_{1.9}$M$_{0.1}$B$_2$ (M= Ge, Ga and Sb) with 20\% excess Al were synthesized by arc…
We present the synthesis and a detailed investigation of structural and magnetic properties of metal-organic compound Cu$_2$(IPA)$_2$(DMF)(H$_2$O) by means of x-ray diffraction, magnetization, and heat capacity measurements. Single crystals…
Sr2IrO4 was predicted to be an unconventional superconductor upon carrier doping since it highly resembles the high-temperature cuprates. Here, to understand carrier doping effect on spin-orbit coupled Mott insulator Sr2IrO4, the electronic…
The magnetization measurements have been performed on the doped spin gap system TlCu_{1-x}Mg_xCl_3 with x <= 0.025. The parent compound TlCuCl_3 is a three-dimensional coupled spin dimer system with the excitation gap Delta/k_B = 7.7 K. The…
Low temperature properties of antiferromagnetic two-leg spin-1/2 ladders with bond randomness and site dilution (or doping with nonmagnetic impurities) are studied using the real-space renormalization-group technique. We find that for non…