Geometrical Phase Transition on WO3_3 Surface

A topographical study on an ensemble of height profiles obtained from atomic force microscopy techniques on various independently grown samples of tungsten oxide WO$_3$ is presented by using ideas from percolation theory. We find that a continuous 'geometrical' phase transition occurs at a certain critical level-height $\delta_c$ below which an infinite island appears. By using the finite-size scaling analysis of three independent percolation observables i.e., percolation probability, percolation strength and the mean island-size, we compute some critical exponents which characterize the transition. Our results are compatible with those of long-range correlated percolation. This method can be generalized to a topographical classification of rough surface models.Comment: 3 pages, 4 figures, to appear in Applied Physics Letters (2010

Bird's-eye view on Noise-Based Logic

Noise-based logic is a practically deterministic logic scheme inspired by the randomness of neural spikes and uses a system of uncorrelated stochastic processes and their superposition to represent the logic state. We briefly discuss various questions such as (i) What does practical determinism mean? (ii) Is noise-based logic a Turing machine? (iii) Is there hope to beat (the dreams of) quantum computation by a classical physical noise-based processor, and what are the minimum hardware requirements for that? Finally, (iv) we address the problem of random number generators and show that the common belief that quantum number generators are superior to classical (thermal) noise-based generators is nothing but a myth.Comment: paper in pres

Conformal Curves on WO3WO_3 Surface

We have studied the iso-height lines on the $\mathrm{WO_3}$ surface as a physical candidate for conformally invariant curves. We have shown that these lines are conformally invariant with the same statistics of domain walls in the critical Ising model. They belong to the family of conformal invariant curves called Schramm-Loewner evolution (or $SLE_{\kappa}$), with diffusivity of $\kappa \sim 3$. This can be regarded as the first experimental observation of SLE curves. We have also argued that Ballistic Deposition (BD) can serve as a growth model giving rise to contours with similar statistics at large scales.Comment: 4 pages, 6 figures. accepted in PR

Оплата праці як елемент виробничої діяльності

Transparent and conducting thin films of TiO2:Nb were prepared on glass and aluminum substrates by dual-target reactive DC magnetron sputtering in an Ar+O-2 plasma. The Nb content lay between 0 and 4.9 at% as determined by ion beam analyses. X-ray diffraction showed that vacuum annealing at 450 degrees C led to crystallinity and prevalence of the anatase phase. The influence of Nb doping was studied with regard to structural, optical, and electrical data. Optical constants were determined from spectrophotometric recordings for films on glass, and the onset of free-electron behavior was documented for annealed films. The latter films, deposited onto Al2O3-coated Al, were found to display optically selective reflectance and to be useful for solar energy applications

Venture capital as a mean of innovation financing in conditions of investment climate volatility in Ukraine

The energy conversion efficiency of a conventional pn junction solar cell decreases as the temperature increases, and this may eventually lead to failures in the photovoltaic system, especially if it uses concentrated solar radiation. In this work, we show that spectrally selective reflector (SSR) surfaces can be important for reducing the heat buildup on passively cooled solar cells. We outline a computational scheme for optimizing DC magnetron-sputtered TiO(2):Nb-based SSRs tailored for silicon solar cells and find good agreement of the reflectance with an experimental realization of the optimal SSR. A figure of merit for SSRs has also been derived and applied to the experimental data

Electron effective mass in Sn-doped monoclinic single crystal β\beta-gallium oxide determined by mid-infrared optical Hall effect

The isotropic average conduction band minimum electron effective mass in Sn-doped monoclinic single crystal $\beta$-Ga$_2$O$_3$ is experimentally determined by mid-infrared optical Hall effect to be $(0.284\pm0.013)m_{0}$ combining investigations on ($010$) and ($\bar{2}01$) surface cuts. This result falls within the broad range of values predicted by theoretical calculations for undoped $\beta$-Ga$_2$O$_3$. The result is also comparable to recent density functional calculations using the Gaussian-attenuation-Perdue-Burke-Ernzerhof hybrid density functional, which predict an average effective mass of $0.267m_{0}$ (arXiv:1704.06711 [cond-mat.mtrl-sci]). Within our uncertainty limits we detect no anisotropy for the electron effective mass, which is consistent with most previous theoretical calculations. We discuss upper limits for possible anisotropy of the electron effective mass parameter from our experimental uncertainty limits, and we compare our findings with recent theoretical results

Диагностика сердечной недостаточности с сохраненной систолической функцией левого желудочка у пациентов с артериальной гипертензией

КАРДИОЛОГИЯГИПЕРТЕНЗИЯСЕРДЕЧНАЯ НЕДОСТАТОЧНОСТЬ ЗАСТОЙНАЯ /ДИАГНОСТИКАИНСТРУКЦИИ ПО ПРИМЕНЕНИ