Ferroelectric field-effect transistor based on ZnO:Li/LiNbO3 and ZnO:Li/TGS heterostructures for IR pyrodetectors

We have developed and studied a new type of pyroelectric IR photodetector based on ferroelectric-field-effect transistor heterostructures with higher sensitivity and detectability than traditional pyroelectric photodetectors. Model samples of ferroelectric field-effect transistor were prepared using ZnO:Li films as a transistor channel and LiNbO₃ or TGS crystals as a pyroelectric sensitive element.     

Impurity absorption in ZnSe/InP/ZnS core/shell/shell spherical quantum dots

Impurity states in ZnSe/InP/ZnS core/shell/shell spherical quantum dot where electrons are localized in the InP shell are considered using variational method. It is assumed that the hydrogenlike impurity is located in the center of quantum dot core (ZnSe). The impurity ground state wave function and energy, as well as electron binding energy are obtained. Interband direct transitions from the ground valence state into the ground donor state are considered. Dependences of absorption edge on the inner and outer radii of the quantum layer are derived.     

Electrophilic and Nucleophilic Addition Reactions of α,β-Unsaturated Diphenylphosphoryl Compounds

Russian Journal of Organic Chemistry - Procedures were developed for the synthesis of diphenyl(prop-1-en-1-yl)phosphine oxide and cyclohex-1-en-1-yl(diphenyl)phosphine oxide by alkaline hydrolysis...     

On recovery of coefficients of Franklin series with a “good” majorant of partial sums

In this paper, we obtain recovery formulas for coefficients of multiple Franklin series by means of its sum, if the series satisfies the following conditions: 1) the square partial sums with indices 2 ^ν converge almost everywhere, 2) the majorant of partial sums with indices 2 ^ν satisfies some necessary condition.     

Estimate of B(B(over) -->Xgamma) at O(alpha(s)2)

Combining our results for various O(alpha[s]) corrections to the weak radiative B-meson decay, we are able to present the first estimate of the branching ratio at the next-to-next-to-leading order in QCD. We find B(B[over ]-->X[s]gamma)=(3.15+/-0.23) x 10(-4) for Egamma>1.6 GeV in the B[over ]-meson rest frame. The four types of uncertainties:nonperturbative (5%), parametric (3%), higher-order (3%), and m(c)-interpolation ambiguity (3%) have been added in quadrature to obtain the total error.     

The melting phenomenon in random-walk model of DNA

The melting phenomenon in a double-stranded homopolypeptide is considered. The relative distance between the corresponding monomers of two polymer chains is modeled by the two-dimensional random walk on the square lattice. Returns of the random walk to the origin describe the formation of hydrogen bonds between complementary units. To take into account the two competing interactions of monomers inside the chains, we obtain a completely denatured state at finite temperature T _c .     

Synthesis of Spiro[benzo[h]chromene-4,3′-indoles] and Spiro[benzo[f]chromene-1,3′-indoles]

Russian Journal of Organic Chemistry - New spiro heterocycles, spiro[benzo[h]chromene-4,3′-indoles] and spiro[benzo[f]chromene-1,3′-indoles], have been synthesized in 50–60% yield...     

NA60 results on thermal dimuons

The NA60 experiment at the CERN SPS has measured muon pairs with unprecedented precision in 158 A GeV In–In collisions. A strong excess of pairs above the known sources is observed in the whole mass region 0.2<M<2.6 GeV. The mass spectrum for M<1 GeV is consistent with a dominant contribution from π ⁺ π ⁻→ρ→μ ⁺ μ ⁻ annihilation. The associated ρ spectral function shows a strong broadening, but essentially no shift in mass. For M>1 GeV, the excess is found to be prompt, not due to enhanced charm production, with pronounced differences to Drell–Yan pairs. The slope parameter T _eff associated with the transverse momentum spectra rises with mass up to the ρ, followed by a sudden decline above. The rise for M<1 GeV is consistent with radial flow of a hadronic emission source. The seeming absence of significant flow for M>1 GeV and its relation to parton–hadron duality is discussed in detail, suggesting a dominantly partonic emission source in this region. A comparison of the data to the present status of theoretical modeling is also contained. The accumulated empirical evidence, including also a Planck-like shape of the mass spectra at low p _T and the lack of polarization, is consistent with a global interpretation of the excess dimuons as thermal radiation. We conclude with first results on ω in-medium effects.     

Pair correlations in sandpile model: A check of logarithmic conformal field theory

We compute the correlations of two height variables in the two-dimensional Abelian sandpile model. We extend the known result for two minimal heights to the case when one of the heights is bigger than one. We find that the most dominant correlation logr/r⁴$\log r/r^4$ exactly fits the prediction obtained within the logarithmic conformal approach.