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The performance effect of splitting and abrupt doping in the drain region, use of a Ge strip at source-channel junction in group IV material based (Ge1 − xSnx/ Si1 − y − zGeySnz) Tunnel Field Effect Transistor (TFET) is investigated in the present manuscript. The variation of certain device parameters, such as mole fraction, different gate dielectrics, gate dielectric thickness and drain doping concentrations are applied to analyze the performance of proposed group IV material based TFET in terms of current-voltage (I-V) characteristics, potential profile and ION/IOFF ratio using device simulator SILVACO TCAD. The simulation results obtained for the proposed TFET structure are compared with the other TFET structures available in the literature, which shows better results as ION/IOFF ratio was received of the order of 1012 in comparison to conventional group IV material based TFET and subthreshold swing of 25.03 mV/decade, which makes the proposed structure promising for high speed switching action with low power CMOS compatibility.

The current research presents a novel third-order nonlinear optical single crystal named diisopropylammonium succinate by slow evaporation solution growth technique. Single-crystal X-ray diffraction and nuclear magnetic resonance techniques are utilized to validate the synthesis and formation of the titled crystal. The grown crystal belongs to monoclinic crystal system with space group P21/n, and its lattice parameters are found to be a = 8.3660 A, b = 11.4818 A, c = 13.5239 A and β = 98.3810°. 1H NMR and 13C NMR revealed the hydrogen bonds present within the molecules of crystal. The 3D visualization of intermolecular interactions was understood by the color contour of Hirshfeld surface of the grown crystal. UV–Vis and photoluminescence spectroscopic techniques are employed to understand the linear optical behavior of the reported crystal. The thermal stability of the material is facilitated by thermogravimetric analysis and differential thermal analysis. The titled crystal is found to be stable up to 140 °C. The third-order nonlinear optical behavior is determined using the z-scan technique.

A near morphotropic phase boundary composition of a new quaternary ceramic 0.47(Bi0.5Na0.5)TiO3–0.04BaTiO3–0.31Pb(Mg1/3Nb2/3)O3–0.18PbTiO3 [BNT–BT–PMN–PT] has been synthesized using the solid state reaction method. The ceramics were characterized for their ferroelectric properties along with dielectric and piezoelectric characteristics. High value of maximum dielectric permittivity (~ 4140) and transition temperature (Tc ~ 190 °C) with low dielectric loss (

Ferroelectricity in pure ZnO nanocrystals is an unlikely physical phenomenon. Here, we show origin of high temperature ferroelectricity in ZnO as a result of yttrium (Y) doping. First, we briefly introduced the wet chemical synthesis of pure and yttrium (Y) doped ZnO nanocrystals. The crystalline phase and morphological appearance of as synthesized pure and Y-doped ZnO nanocrystals were examined using powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. By Y-doing, the morphology of ZnO crystals evolved from 1D nanopencil (pure ZnO) to 3D flower-like architectures assembled by 2D porous nanosheets (Y-ZnO). Crystallite size, deformation stress, energy density and lattice strain of both the nanoparticles were evaluated using Scherrer and Williamson-Hall methods. Frequency as well as temperature dependence of dielectric constant, dielectric loss and ac conductivity of Y-doped ZnO nanosheets were investigated. Ferroelectricity in Y-doped ZnO nanosheets was established using the temperature dependent curve of dielectric constant and the room temperature polarization hysteresis loop. The temperature dependent curve of dielectric constant displayed a ferroelectric to paraelectric transition peak at 138 °C. The Y-ZnO nanosheets exhibit weak ferroelectric polarization hysteresis loop with a remnant polarization (Pr) of 0.09 µC/cm2 and a coercive field (Ec) of 5.87 kV/cm (@ RT). The nature of the leakage present in Y-ZnO sample was extracted from the time-dependent compensasted (TDC) hysteresis study. Leakage current density was found to decrease due to Y-doping in ZnO nanocrystals.

Single crystals of pure and sunset yellow (SSY) dye doped (0.05 mol%) triglycine sulphate (TGS) were grown by slow evaporation solution technique with the vision to improve the properties of pure TGS crystal. The external morphology of TGS crystal was deduced from its internal crystal structure by using two of the well established models, namely Bravais–Friedel–Donnay–Harker model (B–F–D–H) and Hartman–Perdok (H–P) periodic-bound chain (PBC) vectors model. The selective nature of sunset yellow dye to selectively stain the particular growth sectors of TGS crystal was studied. The structural analysis of both the crystals was carried out using powder XRD and FTIR studies. UV–Vis–NIR spectroscopy was carried out on both pure and SSY dyed TGS crystals to study their linear optical properties and various optical parameters namely optical band gap, refractive index, extinction coefficient and optical conductivity were determined. The thermal stability, melting point, ferro- to para-electric transition temperature, piezoelectric charge coefficient, ferroelectricity and mechanical hardness got enhanced as an effect of SSY dye doping in TGS matrix. The piezoelectric conversion efficiency (d22) got enhanced from ~ 56 pm/V for pure TGS single crystal to ~ 85 pm/V for SSY doped TGS single crystal. The true-remanent polarization was determined for dyed TGS crystal using ‘Remanent Hysteresis Task’ which showed the presence of very small contributions of non-switchable components. ‘Time-Dependent Compensated (TDC)’ hysteresis task revealed the absence of resistive leakage in SSY-Doped TGS crystal. The pyroelectric coefficient got enhanced from ~ 761 µCm−2/°C for pure TGS single crystal to ~ 850 µCm−2/°C for SSY doped TGS single crystal. Comparative optical, mechanical, dielectric, piezoelectric, ferroelectric and pyroelectric studies provide useful scientific information of an important class of TGS crystals and suggest SSY-Doped TGS crystal as a better alternative than pure TGS crystal for various opto-electronics and ferroelectric devices applications.

l-Argininium phosphite, nonlinear optical crystal was grown by the slow evaporation solution growth technique. It crystallizes in the monoclinic system, with P21 space group and dimensions of unit cells are a = 9.3677 A, b = 4.8601 A and c = 13.2096 A. Its morphology was simulated and indexed using WinXMorph program. The contribution of different interactions in the crystal structure was discerned visually using Hirshfeld surface analysis. The positions of NMR signal (δ) corresponding to carbon and hydrogen atoms in titled molecule were recorded using HETCOR analysis. Moreover, the titled compound’s crystallinity was examined by performing omega scan. Through UV–Vis–NIR transmittance spectra, the cutoff wavelength and bandgap for titled crystal were evaluated. Its dielectric constant and losses were investigated as frequencies varied at room temperature. Furthermore, laser and shock damage threshold analysis were employed on titled compound. Its piezoelectric charge coefficient was also determined and found to be 12 pC/N along (010) plane. Kurtz and Perry's technique was used to measure its second harmonic generation (SHG) efficiency, which was observed to be 20 mV taking standard KDP as reference.

Organic ferroelectric l-prolinium tartrate (LPT) single crystals have been successfully grown by slow evaporation solution technique. The as-grown LPT crystal has been analyzed by CHN analysis to find the elemental compositions. Single-crystal XRD reveals the monoclinic lattice with non-centrosymmetric space group (P21) as well as cell parameters (a = 5.0071(3) A, b = 17.7056(13) A, c = 6.5371(4) A, β = 100.525(6) °C, and V = 569.79(6) A3). The Hirshfeld surface analysis was carried out to understand various intermolecular interactions in the grown crystal. From temperature-dependent dielectric measurement, a ferroelectric to paraelectric phase transition was observed at 45 °C and a very low (0.05) dielectric loss for higher frequencies (2 MHz) was observed. The FTIR spectroscopy has been carried out in order to identify the different functional groups present in the grown crystal. In ferroelectric studies, P–E hysteresis loops were traced at different temperatures. A high value of piezoelectric charge coefficient (d 33 = 17 pC/N) was found. Vickers hardness test has been used to determine the mechanical strength of the grown crystals and the value of Meyer’s index was found to be n = 1.79 which suggested soft nature of crystals.