相关论文: Violation of the isotropic-$\ell$ approximation in…
Using the Kubo-Greenwood formalism the resistivity anisotropy for electron doped Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$, hole doped (Ba$_{1-x}$K$_x$)Fe$_2$As$_2$ and isovalently doped Ba(Fe$_{1-x}$Ru$_x$)$_2$As$_2$ in their antiferromagnetic state…
The Hall coefficient (R_H) is investigated along the in-plane direction for carefully prepared La_2-x_Sr_x_CuO_4_ thin films from x=0.08 to x=0.40. It is found that R_H becomes almost temperature independent around room temperature for x >=…
We present results of inelastic light scattering experiments on single-crystalline La$_{2-x}$Sr$_{x}$CuO$_4$ in the doping range $0.00 \le x=p \le 0.30$ and Tl$_2$Ba$_2$CuO$_{6+\delta}$ at $p=0.20$ and $p=0.24$. The main emphasis is placed…
I present a new phenomenological model for the normal state transport properties of high-Tc cuprates. In particular, I identify a form of scattering rate that may account, qualitatively and quantitatively, for the normal state…
Electron-doped and hole-doped superconducting cuprates exhibit a symmetric phase diagram as a function of doping. This symmetry is however only approximate. Indeed, electron-doped cuprates become superconductors only after a specific…
High-temperature superconductivity in cuprates emerges upon doping the parent Mott insulator. Robust signatures of the low-doped electronic state include a Hall carrier density that initially tracks the number of doped holes and the…
We study the in-plane resistivity anisotropy in the spin-glass phase of the high-$T_{c}$ cuprates, on the basis of holes moving in a spiral spin background. This picture follows from analysis of the extended $t-J$ model with Coulomb…
We study the anisotropy energy in a planar model for the Cu-O layers of the La2CuO4 investigated in previous works. The Tight-Binding (TB) potential of the model was extended out of the validity region with the purpose of incorporate it in…
We make use of the strong spin-charge coupling in the electron-doped cuprate $\mathrm{Nd}_{2-x}\mathrm{Ce}_x\mathrm{CuO}_4$ to probe changes in its spin system via magnetotransport measurements. We present a detailed study of the…
Despite intense studies the exact nature of the order parameter in superconducting Sr2RuO4 remains unresolved. We have used small-angle neutron scattering to study the vortex lattice in Sr2RuO4 with the field applied close to the basal…
The magnetic and transport properties of La$_{0.5}$Sr$_{0.5}$CoO$_{3-\delta}$ film grown on a LaAlO$_3$ substrate by pulsed-laser deposition are studied. The properties are found to be influenced by a combined influence of the magnetic…
The superconducting properties of high-\tc\ materials are functions of carriers concentration, which is controlled by the concentration of defects including heterovalent cations, interstitial oxygen ions, and oxygen vacancies. Here we…
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…
Efforts to understand the microscopic origin of superconductivity in the cuprates are dependent on knowledge of the normal state. The Hall number in the low temperature, high field limit $n_{\rm H}(0)$ has a particular significance because…
Electron spin resonance data of Cu^{2+} ions in La_{14-x}Ca_{x}Cu_{24}O_{41} crystals (x=9,11,12) reveal a very large width of the resonance line in the paramagnetic state. This signals an unusually strong anisotropy of ~10% of the…
The anisotropy of the superconducting state and superconducting fluctuations in the CuO2 plane is directly related to the superconducting mechanism of copper oxide superconductors and is therefore pivotal for understanding high-temperature…
Raman spectra of La$_{2-x}$Sr$_x$CuO$_4$ are similar to those of Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ except for the split two-magnon peaks at the stripe phase and the stronger step-like decrease in the low energy $B_{\rm 2g}$ spectra. The…
We measure the penetration depth of optimally doped and underdoped La2-xCexCuO4 in the millimeter frequency domain (4 - 7 cm-1) and for temperatures 2 K < T < 300 K. The penetration depth as function of temperature reveals significant…
Electron-hole pair excitations in the insulating cuprates $Sr_2CuO_2Cl_2$ were investigated by angle-resolved electron energy loss spectroscopy. The optically allowed and optically forbidden transitions were observed to be strongly…
We describe the high-temperature superconductor La$_{2-x}$Sr$_x$CuO$_4$ in the underdoped regime in terms of a mixed-phase model, which consists of superconducting clusters embedded in the antiferromagnetic matrix. Our work is motivated by…