We argue that the scanning tunneling microscope (STM) images of resonant states generated by doping Zn or Ni impurities into Cu-O planes of BSCCO are the result of quantum interference of the impurity signal coming from several distinct paths. The impurity image seen on the surface is greatly affected by interlayer tunneling matrix elements. We find that the optimal tunneling path between the S...

In spite of the considerable efforts to explain the experimental Raman spectra of cuprate superconductors, the A1g superconducting response is not yet completely understood. It has been shown that the theoretical description of the A1g Raman response was very sensitive to small changes in the Raman vertex harmonic representations, yielding peak positions varying between ∆ and 2∆ [1]. However, t...

We consider a bilayer version of the extended t-J model, with a view to computing the form of certain experimentally observable properties. Using the slave-boson decomposition , we show at the mean-field level that in the bilayer system the existence of in-plane d-wave singlet pairing excludes any interplane singlet order for reasonable values of the interplane superexchange parameter. Restrict...

We study the thermal fluctuations of anisotropic order parameters (OP) in lay-ered superconductors. In particular, for copper oxides and a d-wave OP, we present some experimental consequences of fluctuations in the direction normal to the layers. It is shown that the c-axis penetration depth λ c can have a " disorder-like " quadratic temperature dependence at low temperature. The fluctuations a...

Ž . Melt-processing of BSCCO high-T superconductors HTS under an elevated magnetic field is an effective technique for c producing superconductors with enhanced critical current. This result is a consequence of the high degree of crystallographic texture achieved in the polycrystalline superconductor processed under a high magnetic field. Possible mechanisms for the orientation of Bi-2212 plate...

0031-9007= The cuprate material Bi2Sr2CaCu2O8 (BSCCO-2212) is believed to be doped by a combination of cation switching and excess oxygen. The interstitial oxygen dopants are of particular interest because scanning tunneling microscopy (STM) experiments have shown that they are positively correlated with the local value of the superconducting gap, and calculations suggest that the fundamental a...

We describe the design of a wide temperature range (300 mK-300 K) atomic force microscope/magnetic force microscope with a self-aligned fibre-cantilever mechanism. An alignment chip with alignment groves and a special mechanical design are used to eliminate tedious and time consuming fibre-cantilever alignment procedure for the entire temperature range. A low noise, Michelson fibre interferomet...

The zero temperature vortex phase diagram for uniaxial anisotropic superconductors placed in an external magnetic field tilted with respect to the axis of anisotropy is studied for parameters typical of BSCCO and YBCO. The exact Gibbs free energy in the London approximation, using a self-energy expression with an anisotropic core cutoff, is minimized numerically, assuming only that the equilibr...