On the nature of doping effect of methane in ZnO thin films deposited by RF-magnetron sputtering

Journal of Materials Science: Materials in Electronics - A comparative study of the effects of methane and hydrogen as reactive agents on the structural, optical, and electrical properties of ZnO...     

Application of the Darboux transform to spectral problems in ocean acoustics

We propose a generalization of the n-order Darboux transform, which can be applied to solving spectral problems in ocean acoustics in cases when the medium can be considered stratified with respect to density. For a second-order Darboux transform with the boundary conditions characteristic of a single-layer shallow sea model, conditions are determined under which the spectra of the initial and transformed spectral problems coincide. It is demonstrated that, within the framework of this model, it is possible to use the n-order Darboux transform for constructing sound velocity profiles admitting exact solutions.     

Tunneling conductance of break junction with the (100) plane fracture surface of Bi2Sr2CaCu2O8

Using the new method of breaking, the tunnel junctions with the (100) plane fracture surface could be obtained. The observed singularities in conductivity can be explained by tunneling between the different layers (CuO₂→CuO₂, sharp peaks at 2Δ _p−p =64±2mV;CuO ₂→BiO, peaks at 100–140 mV; BiO→BiO, wide maxima at about 250 mV). The tunneling spectra measured at T=4.2–100 K show that a shift of the 2Δ _p−p peak to lower biases is much stronger (from 64 to 37 mV) than the BCS prediction at T/T_c≤0.7. At higher T (up to T_c≈87K) the changes of the spectra look like those expected for gapless superconductivity in agreement with the ARPES data for a-direction.