Effects of Annealing on Structural Properties of Copper Zinc Tin Sulphide (CZTS) Material

Copper Zinc Tin Sulphide compound was synthesized from its elemetal precursurs using simple solid state method. Being quarternary material, there is a large probability of formation of secondary phases like SnS, ZnS, CuS during the material growth process and it requires a detail investigation on the effects of synthesis parameters on the composition and structural properties of the CZTS compound. Here we report the study of effects of annealing on the synthesized compound. The annealing was performed at two different temperatures in the presence of Sulphur. The structural and compositional properties of the as-grown and annealed samples were examined by X-ray diffraction (XRD) and Energy Dispersive Analysis of X-Ray (EDAX). The formation of Kesterite CZTS phase was confirmed by Raman Spectroscopy. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3102

Effects of Annealing on Structural Properties of Copper Zinc Tin Sulphide (CZTS) Material

Copper Zinc Tin Sulphide compound was synthesized from its elemetal precursurs using simple solid state method. Being quarternary material, there is a large probability of formation of secondary phases like SnS, ZnS, CuS during the material growth process and it requires a detail investigation on the effects of synthesis parameters on the composition and structural properties of the CZTS compound. Here we report the study of effects of annealing on the synthesized compound. The annealing was performed at two different temperatures in the presence of Sulphur. The structural and compositional properties of the as-grown and annealed samples were examined by X-ray diffraction (XRD) and Energy Dispersive Analysis of X-Ray (EDAX). The formation of Kesterite CZTS phase was confirmed by Raman Spectroscopy. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3102

Surfactant Free Synthesis and Study of Vanadium Pentoxide Nanostructure

The varied oxidation state and layered structure are two importance features of vanadium pentoxide which makes it more special. Here, vanadium pentoxide nanostructure has been synthesized by a surfactant free and ecofriendly method using ammonium vanadate as a precursor salt. Synthesized nanostructure were characterized using X-ray diffraction method (XRD), Energy Dispersive X-Ray Analysis (EDAX), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and UV-Visible spectroscopy to study its structural, compositional, morphology, vibrational modes and optical behavior. XRD and FTIR confirm the orthorhombic phase of the vanadium pentoxide with a layered structure of irregular plates as observed from the SEM micrograph. Moreover, the band gap of material is 2.13 eV as evaluated from UV-Visible data

Statistics of Coulomb blockade peak spacings for a partially open dot

We show that randomness of the electron wave functions in a quantum dot contributes to the fluctuations of the positions of the conductance peaks. This contribution grows with the conductance of the junctions connecting the dot to the leads. It becomes comparable with the fluctuations coming from the randomness of the single particle spectrum in the dot while the Coulomb blockade peaks are still well-defined. In addition, the fluctuations of the peak spacings are correlated with the fluctuations of the conductance peak heights.Comment: 13 pages, 1 figur

Decoherence in rf SQUID Qubits

We report measurements of coherence times of an rf SQUID qubit using pulsed microwaves and rapid flux pulses. The modified rf SQUID, described by an double-well potential, has independent, in situ, controls for the tilt and barrier height of the potential. The decay of coherent oscillations is dominated by the lifetime of the excited state and low frequency flux noise and is consistent with independent measurement of these quantities obtained by microwave spectroscopy, resonant tunneling between fluxoid wells and decay of the excited state. The oscillation's waveform is compared to analytical results obtained for finite decay rates and detuning and averaged over low frequency flux noise.Comment: 24 pages, 13 figures, submitted to the journal Quantum Information Processin

Deposition and Characterization of Indium Selenide Thin Films for Opto-electronic Devices

Amongst all the III-VI semiconductors, ones that crystallize with a layered structure have gained special interest due to its significant usage in photovoltaic devices. III-VI layered semiconductor such as InSe has low density of dangling bonds on its surface therefore it is considered as vital material for the fabrication of opto-electronic devices like photo sensor, solar cell etc. In present work, InSe thin films were fabricated through a simple and facile drop-casting method, where the thin films were drop-casted between two silver paste electrodes on a glass substrate. The structural, surface morphological, compositional, electrical and optical properties of the prepared films were obsrved by XRD, SEM, EDAX, high precision digital multi-meter and UV-visible spectroscopy, respectively. XRD analysis of the prepared film shows the existence of nano-crystalline nature with monoclinic crystal structure of InSe. SEM images show good continuity of InSe film. InSe thin films are n-type with bandgap of 1.8 eV and their electrical conductivity is in the order of 10 – 10 S/cm that makes them appropriate for using as an absorber layer in the solar cell

Anisotropy studies around the galactic centre at EeV energies with the Auger Observatory

Data from the Pierre Auger Observatory are analyzed to search for anisotropies near the direction of the Galactic Centre at EeV energies. The exposure of the surface array in this part of the sky is already significantly larger than that of the fore-runner experiments. Our results do not support previous findings of localized excesses in the AGASA and SUGAR data. We set an upper bound on a point-like flux of cosmic rays arriving from the Galactic Centre which excludes several scenarios predicting sources of EeV neutrons from Sagittarius $A$. Also the events detected simultaneously by the surface and fluorescence detectors (the `hybrid' data set), which have better pointing accuracy but are less numerous than those of the surface array alone, do not show any significant localized excess from this direction.Comment: Matches published versio

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC

Measurements of inclusive jet suppression in heavy ion collisions at the LHC provide direct sensitivity to the physics of jet quenching. In a sample of lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the anti-kt algorithm with values for the distance parameter that determines the nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp. Jet production is found to be suppressed by approximately a factor of two in the 10% most central collisions relative to peripheral collisions. Rcp varies smoothly with centrality as characterized by the number of participating nucleons. The observed suppression is only weakly dependent on jet radius and transverse momentum. These results provide the first direct measurement of inclusive jet suppression in heavy ion collisions and complement previous measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables, submitted to Physics Letters B. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02