Related papers: Systematic X-ray absorption study of hole doping i…
The effects of non-magnetic iso-valent defects inside the CuO2 plane(s) on superconducting transition temperature, Tc, dc charge transport, and the bulk magnetic susceptibility, \c{hi}(T), were investigated for the YBa2(Cu1-yZny)3O7-d…
Scanning tunneling spectroscopy was performed on c-axis Y{1-x}Ca{x}Ba2Cu3O{7-delta} thin films for x= 0, 0.05, 0.15 and 0.20 at 4.2K. The measured spectra show main-gap, sub-gap and satellite features which scale similarly in energy versus…
The phase diagram of LaFeAs$_{1-x}$P$_x$O system has been extensively studied through hole- and electron-doping as well as As/P-substitution. It has been revealed that there are three different superconducting phases with different Fermi…
Bright and eclipsing, the high-mass X-ray binary Vela X-1 offers a unique opportunity to study accretion onto a neutron star from clumpy winds of O/B stars and to disentangle the complex accretion geometry of these systems. In Chandra-HETGS…
We measure the magnetic-field dependence of the c-axis resistivity, \rho_c(H), in a series of Bi_{2}Sr_{2-x}La_xCuO_{6+\delta} (BSLCO) single crystals for a wide range of doping using pulsed magnetic fields up to 58 T. The behavior of…
The effect of Zn substitution on the superconducting transition temperature, Tc, was investigated for the sintered Y1-xCaxBa2(Cu1-yZny)3O7-delta compounds over a wide range of hole concentration per CuO2 plane, p. Ca substitution enabled us…
We have measured the superconducting gap Ds in optimally doped samples of BSCCO, TBCCO, HBCCO and HSCCO by Andreev and tunnelling spectroscopy and by ARPES. We have found that the low-temperature value of the gap within experimental errors…
The critical current density Jc in high-Tc superconductors (HTS) often shows a maximum at field far above the self-field. We study this peak effect(PE) with the nonlinear I-V response of type-II superconductors and find analytical equation…
It is widely believed that, in contrast to its electron doped counterparts, the hole doped compound Ba1-xKxFe2As2 exhibits a mesoscopic phase separation of magnetism and superconductivity in the underdoped region of the phase diagram. Here,…
Cerium-doped manganite thin films were grown epitaxially by pulsed laser deposition at $720 ^\circ$C and oxygen pressure $p_{O_2}=1-25 $Pa and were subjected to different annealing steps. According to x-ray diffraction (XRD) data, the…
The transition metal K-edge x-ray absorption near edge structure (XANES) studies have been carried on LaBO3 (B=Mn, Fe, Co, Ni), La2CuO4 and SrMnO3 compounds. The theoretical spectra have been calculated using transition metal (TM) 4p…
Magnetic measurements on heavily overdoped $La_{2-x}Sr_xCuO_4$, $Tl_2Ba_2CuO_6$, $Bi_2Sr_2CuO_6$ and $Bi_2Sr_2CaCu_2O_8$ single crystals reveal a new type magnetization hysteresis loops characterized by the vanishing of usual central peak…
Band calculations for the hole doped La$_2$CuO$_4$ system show that artificial periodicities of Ba dopants can give the material different properties than from a uniform distribution of dopants. A periodicity within the planes make static…
High quality large Bi$_2$Sr$_{2-x}$La$_{x}$CuO$_6$(La-Bi2201) single crystals have been successfully grown by the traveling solvent floating zone technique. The samples are characterized by compositional and structural analyzes and their…
We have made a high-resolution photoemission study of La2-xSrxCuO4 in a wide hole concentration (x) range from a heavily overdoped metal to an undoped insulator. As x decreases, the spectral density of states at the chemical potential (\mu)…
We measured the thermopower S and the Hall coefficients R_H of Bi_{2}Sr_{2-z}La_{z}CuO_{6+\delta} (BSLCO) single crystals in a wide doping range, in an effort to identify the actual hole concentrations per Cu, p, in this system. It is found…
We apply a method recently derived based on the extended Hubbard Hamiltonian and the BCS approach to obtain the superconducting critical temperature dependence with carrier density for the HgBaCuO compounds. We show that this procedure can…
The optical properties the high-temperature superconductor La{2-x}Ba{x}CuO{4} have been measured over a wide frequency and temperature range for light polarized in the a-b planes and along the c axis. Three different Ba concentrations have…
Measurements of thermal conductivity versus temperature over a broad range of doping in YBa$_2$Cu$_3$O$_{6+x}$ and HgBa$_2$Ca$_{n-1}$Cu$_n$O$_{2n+2+\delta}$ ($n$=1,2,3) suggest that small domains of localized holes develop for hole…
The in-plane resistivity and Hall coefficient have been measured for the single-layer compound Bi$_2$Sr$_2$CuO$_{6+\delta}$ for the whole range of doping states. The deviation of the Hall coefficient, $R_H$, from a high-temperature linear…