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In this letter, we have investigated the RF performance of a negative capacitance FinFET (NC-FinFET) using BSIM-CMG compact model extracted from DC and RF measured data of 10-nm technology node devices. This physics-based RF model is then coupled self-consistently with the Landau-Khalatnikov equation to obtain the RF NC-FinFET model. For the first time, we report, here, the impact of ferroelectric thickness ( ${t}_{\textit {fe}}$ ) scaling on RF performance of NC-FinFET and find that NC-FinFET’s cut-off frequency ( ${f}_{\text {T}}$ ) is a function of ${t}_{\textit {fe}}$ . We also observe that the self-heating effect in NC-FinFET increases with increase in ${t}_{\textit {fe}}$ , mainly due to increase in DC current, which can be easily compensated by decreasing supply voltage. Finally, we show that NC-FinFET can achieve similar analog/RF performance as the base FinFET, even at a reduced ${V}_{\mathrm{ DD}}$ .

Field experiment was consecutively conducted for two years on deep alluvial clay loam soil (Typic haplustept) with three levels of water regimes and four levels of nitrogen in rice-wheat cropping system. Integrated effect of water and nitrogen levels depicted the rice and wheat grain yield of 3.55 and 3.41 Mg/ha respectively. Individually, grain yield increased by 104.9 and 70.3% respectively for rice and wheat with increasing N levels from 0-180 kg/ha. A reduction of 9.6 and 19.7% in grain yield was observed with change in treatment of water regimes from W1 to W2 and W1 to W3 in rice. The corresponding values for wheat were 6.3 and 13.7%, respectively. The simulation study, carried out by calibrating and validating the CropSyst model, showed the simulation yields were in agreement with observed yields as was evident by high correlation coefficient (0.87 - 0.96) and modeling efficiency (0.79 - 0.95) at all water regimes and nitrogen levels for biomass and grain yield. Also, the root mean square error (RMSE) for biomass and grain yield was 5 and 9% of the observed mean in rice which was 3 and 18% for wheat indicating that the model is accurate in predicting these two initial parameters. The model was tested for accuracy in determining the crop parameters by conducting sensitivity analysis which depicted that the above ground biomass conversion, optimum mean daily temperature and phenological degree days needs more accuracy in simulation. Pooled experimental data of the two years showed that substantial water saving can be done but the yield was reduced by 9.6 and 19.7% in rice and 6.3 and 13.7% in case of wheat which can be neglected at the time of rising global water stress.

Water budgeting studies under different rice cultivation methods provides an insight into the amount of water used by the plant and percolated below the root zone for judicious water management. To undertake this study, a field experiment was conducted to estimate different soil water balance parameters under three rice (Oryza sativa L.) cultivation methods viz. Direct Seeded Rice (DSR), System of Rice Intensification (SRI) and Conventional Puddled Rice (CPR). The experiment was conducted during kharif 2013 and kharif 2014 season at research farm of Indian Council of Agricultural Research-Indian Agricultural Research Institute, New Delhi, India. In this study, the rainfall and irrigation depth, Crop Evapotranspiration (ETc), percolation beyond root zone of the crop and surface runoff during the crop growth period were accounted in water budgeting. It was observed that the percolation be-yond root zone of the crop was the highest under CPR method amounting 963 mm and 831 mm, which was about 55% and 58% of total water applied during 2013 and 2014, respectively. However, the percolation beyond root zone of the crop was the lowest under DSR method of rice cultivation amounting 367 mm and 332 mm which was 43% and 39% of total water applied during 2013 and 2014, respectively. Water loss through Etc was around 30% of total water applied in all three cultivation methods for year 2013. However, it was 59%, 46% and 43% of total water ap-plied for DSR, SRI and CPR, respectively in the year 2014.This indicates more effective utilization of total applied water in the year 2014.The study highlighted that water loss through deep percolation beyond root zone is the major factor contributing to the high water requirement in CPR and SRI methods compare to DSR method. Moreover, different soil water balance components computed in this study will be helpful for estimation of irrigation water requirement in the rice growing areas of the agro-climatic region VI (Trans-gangetic Plains) of India.

An experiment was conducted with aim to investigate the effect of sowing dates and irrigation regimes on wheat grain quality. There was four sowing dates [November 1(S1), November 16 (S2), December 1(S3) and December 16 (S4)], in main plots and four irrigation regimes [25% (I1), 50% (I2) and 75% (I3) maximum allowable depletion (MAD) of available soil moisture (ASM) and I4 – four critical growth stages in sub plots. The results revealed that hectolitre weight decreased from 80.2 and 81.4 kg hl-1 in S1 treatment to 78.3 and 79.4 kg hl-1 in S4 treatment and 79.9 and 81.5 kg hl-1 in I1 treatment to 79.0 and 79.9 kg hl-1 in I3 treatment in 2010-11 and 2011-12, respectively. Grain hardness outcome was ≥75 in 2010-11 while it was

The authors have evaporated submonolayer to monolayer Sb films on the clean Au(110) surface and investigated the resultant Sb-induced reconstructions using low energy electron diffraction, x-ray photoelectron spectroscopy, Auger electron spectroscopy, and surface x-ray diffraction. They discovered a sequence of reconstructions, namely, c(2×2), (3×3)R54.7°, (2−112), and p(5×6), with increasing coverage of Sb. The well-known (2×1) reconstruction of the clean Au(110) surface changes to c(2×2) at an Sb coverage of θ≈0.5 ML. At higher Sb coverages, there is a phase transition from c(2×2) to (3×3)R54.7°, with the (3×3)R54.7° pattern emerging at an Sb coverage of θ≈0.7 ML. Upon further deposition, the superstructure spots of the (3×3)R54.7° reconstruction each split into two, resulting in the (2−112) pattern at a coverage of θ≈0.8 ML. Finally, an Sb∕Au(110)-p(5×6) reconstruction emerges at coverages in excess of 1 ML. They have also studied the temperature dependence of the c(2×2) surface phase.

The discovery that the phase problem of diffraction from non-periodic objects may be solved by oversampling the diffraction intensities in reciprocal space with respect to a Nyquist criterion has opened up new vistas for structure determination by diffraction methods. A similar principle may be applied to the problem of surface X-ray diffraction (SXRD), where, owing to the breaking of a crystal periodicity normal to its surface, diffraction data consist of a set of superstructure rods (SRs) due to scattering from the parts of the surface whose structure is different from that of the truncated bulk and of crystal truncation rods (CTRs), formed by interfering contributions from the surface and the bulk. A phase and amplitude recovery and diffraction image generation method (PARADIGM) is described that provides a prescription for finding the unmeasured amplitudes and phases of the surface contributions to the CTRs in addition to the phases of the SRs, directly from the diffraction data. The resulting `diffraction image' is the basis of a determination of the previously unknown multidomain structure of Sb/Au(110)–√3 × √3R54.7°.

Adsorption of 0.5 monolayers (ML) of Sb on the Au(1 1 0) surface resulted in the formation of a c(2 x 2) surface reconstruction. Analysis of surface X-ray diffraction data by a direct method revealed the existence of an ordered substitutional surface alloy, with every other hollow site occupied by Au and Sb atoms. Quantitative conventional {chi}{sup 2} refinement showed a contraction of 0.12 {+-} 0.03 Angstroms in the spacing of the first Au layer to the second, an expansion of 0.13 {+-} 0.03 Angstroms in the second-to-third layer distance, and an inward Sb displacement (rumpling) of 0.21 {+-} 0.04 Angstroms. This surface phase proved to be extremely robust, with the long-range order of this arrangement remaining up to substrate temperatures of 900 K.

We present an experimental and theoretical study of the geometric structure of ultrathin BaTiO(3) films grown on Fe(001). Surface x-ray diffraction reveals that the films are terminated by a BaO layer, while the TiO(2) layer is next to the top Fe layer. Cations in termination layers have incomplete oxygen shells inducing strong vertical relaxations. Onset of polarization is observed at a minimum thickness of two unit cells. Our findings are supported by first-principles calculations providing a quantitative insight into the multiferroic properties on the atomic scale.

The geometric structure of O/Fe(001)-p(1x1) is studied by surface x-ray diffraction (SXRD). After dosing of about 4 L (1 L = 10(-6) Torr s) of oxygen at room temperature we find approximately one monolayer (ML) of oxygen in an FeO-like structure forming two layer thick islands covering about 40% of a roughened Fe(001) surface. Subsequent annealing up to 500 C results in surface flattening leading to a highly ordered structure. Very precise SXRD data reveal the presence of 1 ML of oxygen atoms located in fourfold hollow sites at d((O-Fe)) = 0.48 +/- 0.08 angstrom above the first Fe layer. The first Fe-Fe-interlayer spacing is expanded to d(12) = 1.66 +/- 0.02 angstrom corresponding to an increase of 16% relative to the bulk spacing (1.43 angstrom). Density-functional calculations confirm our findings and indicate a strong dependence of the (local) layer expansion on the oxygen coverage. Our results are important for understanding the surface magnetic properties of the O/Fe(001)-p(1x1) surface in general.

The discovery that the phase problem of diffraction from non-periodic objects may be solved by oversampling the diffraction intensities in reciprocal space with respect to a Nyquist criterion has opened up new vistas for structure determination by diffraction methods. A similar principle may be applied to the problem of surface X-ray diffraction (SXRD), where, owing to the breaking of a crystal periodicity normal to its surface, diffraction data consist of a set of superstructure rods (SRs) due to scattering from the parts of the surface whose structure is different from that of the truncated bulk and of crystal truncation rods (CTRs), formed by interfering contributions from the surface and the bulk. A phase and amplitude recovery and diffraction image generation method (PARADIGM) is described that provides a prescription for finding the unmeasured amplitudes and phases of the surface contributions to the CTRs in addition to the phases of the SRs, directly from the diffraction data. The resulting ;diffraction image' is the basis of a determination of the previously unknown multidomain structure of Sb/Au(110)-radical3xradical3R54.7 degrees.

A solution to the phase problem for the case of surface crystallography is presented. By oversampling a surface diffraction pattern along the continuous crystal-truncation rods, we can iteratively recover the phases of the complex structure factors of an unknown surface atomic geometry. Simple Fourier inversion of these structure factors directly yields a three-dimensional map of the electron density in the surface region with {approx}A resolution. This model-independent determination of atomic positions can then be used as a starting point for quantitative refinement using conventional means.

The solid-state reaction of thick $(\ensuremath{\sim}50\phantom{\rule{0.3em}{0ex}}\text{nm})$ and thin $(\ensuremath{\sim}\text{monolayer})$ films of Hf with cleaned and oxidized $\text{Si}(001)$ substrates was investigated. Upon annealing to $1000\phantom{\rule{0.2em}{0ex}}\ifmmode^\circ\else\textdegree\fi{}\mathrm{C}$, films of ${\text{HfSi}}_{2}$ were formed after reaction times that depended upon the surface condition of the substrate before deposition. The chemical state of the reacted surfaces was characterized using x-ray photoelectron spectroscopy, and the shifts in binding energy upon silicide formation were recorded. Even for thick films, low-energy electron diffraction (LEED) revealed that the $(2\ifmmode\times\else\texttimes\fi{}1)$ pattern of the Si substrate emerged, suggesting that three-dimensional islanding of the ${\text{HfSi}}_{2}$ film had occurred. The islanding behavior was investigated for both thick and thin films using LEED, atomic force microscopy, and scanning electron microscopy. Streaking in the LEED patterns for the thick films suggest that the island morphology is influenced by the underlying Si substrate.

Numerous allelochemicals belonging to various groups of secondary metabolites viz. nonprotein amino acids, cyanogens, phenolic compounds and alkaloids reported from promising leguminous forages and involved in plant - animal and plant-plant interactions are reviewed. Their ecological significance has also been discussed.

Ag was examined as a potential surfactant to aid in the growth of smooth Co films deposited on MgO. Ag was deposited onto single-crystal MgO(111)-(3×3)R30° substrates. It was found that Ag formed islands upon annealing. Monolayer films of Co were subsequently deposited using an electrostatic electron-beam evaporator on single-crystal MgO(111)-(3×3)R30° substrates with 0.5–10 monolayers of Ag. The Ag/MgO substrates were held at room temperature or 450 °C during growth, with subsequent annealing of temperatures 400–800 °C. These films have been characterized using low-energy electron diffraction, x-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). Despite the fact that Ag formed islands, it was found that the presence of Ag did have a surfactant effect upon the thin-film growth of Co on Ag/MgO(111)-(3×3)R30°. Co islands were still present, but the surface was much smoother than for films grown without the Ag surfactant. XPS peak intensity changes and AFM suggest strongly that Ag segre...