Top-Gated Chemical Vapor Deposited Mos2 Field-Effect Transistors On Si3N4 Substrates

We report the electrical characteristics of chemical vapor deposited (CVD) monolayer molybdenum disulfide (MoS2) top-gated field-effect transistors (FETs) on silicon nitride (Si3N4) substrates. We show that Si3N4 substrates offer comparable electrical performance to thermally grown SiO2 substrates for MoS2 FETs, offering an attractive passivating substrate for transition-metal dichalcogenides (TMD) with a smooth surface morphology. Single-crystal MoS2 grains are grown via vapor transport process using solid precursors directly on low pressure CVD Si3N4, eliminating the need for transfer processes which degrade electrical performance. Monolayer top-gated MoS2 FETs with Al2O3 gate dielectric on Si3N4 achieve a room temperature mobility of 24 cm(2)/V s with I-on/I-off current ratios exceeding 10(7). Using HfO2 as a gate dielectric, monolayer top-gated CVD MoS2 FETs on Si3N4 achieve current densities of 55 mu A/mu m and a transconductance of 6.12 mu S/mu m at V-tg of -5V and V-ds of 2V. We observe an increase in mobility at lower temperatures, indicating phonon scattering may dominate over charged impurity scattering in our devices. Our results show that Si3N4 is an attractive alternative to thermally grown SiO2 substrate for TMD FETs. (C) 2015 AIP Publishing LLC.STTR programNSF NASCENT ERCArmy Research Office under STTR W911NF-14-P-0030Microelectronics Research Cente

Development of high efficiency solar cells on silicon web

Web base material is being improved with a goal toward obtaining solar cell efficiencies in excess of 18% (AM1). Carrier loss mechanisms in web silicon was investigated, techniques were developed to reduce carrier recombination in the web, and web cells were fabricated using effective surface passivation. The effect of stress on web cell performance was also investigated

Spectroscopic properties of Sm3+ and CdS co-doped in sol-gel silica glass

157-163Sm3+- doped silica glass co-doped with CdS nanoparticles have been prepared by sol-gel method. FTIR spectra of the samples at different annealing temperatures show the gradual removal of hydroxyl group. XRD pattern shows crystalline nature of the silica host along with CdS peak. The optical absorption and fluorescence properties have been investigated using Judd-Ofelt theory. The Judd-Ofelt intensity parameters have been obtained from the absorption spectrum following the trend Ω2 > Ω4 > Ω6 and the large value of Ω2 indicates covalency of the rare earth bonding. Under excitation with 370 nm, photoluminescence peaks have been observed in the green, yellow, orange and red region as a result of radiative relaxation from the 4G5/2 state

Molecular approaches towards assessment of cyanobacterial biodiversity

No Abstrac

Economic Efficiency Measure of Induction Motors for Industrial Applications

This paper, introduced an expression of Economic Efficiency Measure (EEM) to permit quick evaluation for replacement of faulty induction motor with alternative (new or refurbished motor) for lowest life-cycle cost based on efficiency and rated-load conditions. This approach, simplifies the process for evaluating the energy efficiency to mere proportionate factor called as EEM. During the operating phase, the motor losses correspond to extra energy consumption, based on various parameters like motor operating conditions, operating hours, operating costs, fault factor, depreciation factor and fixed costs.  The approach is effective in addressing the global issue on replacement of the faulty motor that needs a comprehensive analysis and mathematical expression. Compared to other alternatives the EEM provides a simple but effective and reliable means to asses, the feasibility of replacing or refurbishing the faulty motor. A detail analysis here would establish how much the present approach is effective in determining the replacement for a faulty induction motor either by a new one or refurbished one of corresponding rating

Lepton flavour violation in The Little Higgs model

Little Higgs models with T-parity have a new source of lepton flavour violation. In this paper we consider the anomalous magnetic moment of the muon \gmtwo and the lepton flavour violating decays \mutoeg and \tautomug in Little Higgs model with T-parity \cite{Goyal:2006vq}. Our results shows that present experimental constraints of \mutoeg is much more useful to constrain the new sources of flavour violation which are present in T-parity models.Comment: LaTeX file with 13 eps figures (included

Dissociative Autoionization in (1+2)-photon Above Threshold Excitation of H2 Molecules

We have theoretically studied the effect of dissociative autoionization on the photoelectron energy spectrum in (1+2)-photon above threshold ionization(ATI) of H2 molecules. We have considered excitation from the ground state X-singlet-Sigma-g+(v=0,j) to the doubly excited autoionizing states of singlet-Sigma-u+ and singlet-Pi-u+ symmetry, via the intermediate resonant B-singlet-Sigma-u+(v=5,j) states. We have shown that the photoelectron energy spectrum is oscillatory in nature and shows three distinct peaks above the photoelectron energy 0.7 eV. This feature has been observed in a recent experiment by Rottke et al, J. Phys. B, Vol. 30, p-4049 (1997).Comment: 11 pages and 4 figure

On Some properties of Di-hadronic states

The binding energies of di- hadronic states have been calculated assuming a 'molecular' interaction provided by the asymptotic expression of the residual confined gluon exchange potential between the component hadrons in the system. Meson- meson and meson- baryon states have been studied in detail and a mass formula has been used to calculate total mass of the 'molecules'.Comment: 11 page

Symmetry in cancer networks identified: Proposal for multicancer biomarkers

One of the most challenging problems in biomedicine and genomics is the identification of disease biomarkers. In this study, proteomics data from seven major cancers were used to construct two weighted protein–protein interaction networks, i.e., one for the normal and another for the cancer conditions. We developed rigorous, yet mathematically simple, methodology based on the degeneracy at –1 eigenvalues to identify structural symmetry or motif structures in network. Utilizing eigenvectors corresponding to degenerate eigenvalues in the weighted adjacency matrix, we identified structural symmetry in underlying weighted protein–protein interaction networks constructed using seven cancer data. Functional assessment of proteins forming these structural symmetry exhibited the property of cancer hallmarks. Survival analysis refined further this protein list proposing BMI, MAPK11, DDIT4, CDKN2A, and FYN as putative multicancer biomarkers. The combined framework of networks and spectral graph theory developed here can be applied to identify symmetrical patterns in other disease networks to predict proteins as potential disease biomarkers