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Operation voltage reduction and gain enhancement in organic CMOS inverters with the TTC/gelatin bilayer dielectric
An air ambient operated organic complementary metal oxide semiconductor (CMOS) inverter has been fabricated on poly(ethylene terephthalate) (PET) using pentacene and N,N-dioctyl-3,4,9,10-perylene tetracarboxylic diimide (PTCDI-C8) as active layers with a bilayer dielectric of tetratetracontane (C) and gelatin. The inverter performance is greatly improved by replacing the gelatin dielectric with...


Atomistic study on dithiolated oligo-phenylenevinylene gated device
Thanks to their semiconducting behavior, conjugated molecules are considered as an attractive candidate for future electronic devices. Understanding the charge transportcharacteristics through such molecules for different device applications would accelerate the progress in the field of molecular electronics. In addition, it would become more feasible to introduce/enhance specific properties of...
Anisotropic magnetocaloric effect in TmAl2 single crystal
In this paper, we theoretically discuss the anisotropic magnetocaloriceffect in TmAl2single crystal. To this end, we use a model Hamiltonian of interacting magnetic moments including an extra term to account for the crystal electric field. Our theoretical calculations are in a reasonable agreement with the available experimental data. Moreover, we predict the existence of an anomalous anisotrop...


Development of a microwave capacitive method for the spectroscopy of the complex permittivity
We describe a vector network analyzer-based method to study the electromagnetic properties of nanoscale dielectrics at microwave frequencies (1 MHz–40 GHz). The complex permittivity spectrum of a given dielectric can be determined by placing it in a capacitor accessed on its both electrodes by coplanar waveguides. However, inherent propagation delays along the signal paths together with frequ...
Direct imaging of thermally-activated grain-boundary diffusion in Cu/Co/IrMn/Pt exchange-bias structures using atom-probe tomography
Magnetic devices are often subject to thermal processing steps, such as field cooling to set exchange bias and annealing to crystallize amorphous magnetic electrodes. These processing steps may result in interdiffusion and the subsequent deterioration of magnetic properties. In this study, we investigated thermally-activated diffusion in Cu/Co/IrMn/Pt exchange biased polycrystalline thin-film s...


Enhancing the orthorhombicity and antiferromagnetic-insulating state in epitaxial La0.67Ca0.33MnO3/NdGaO3(001) films by inserting a SmFeO3 buffer layer
Structural and magnetotransport properties of epitaxial La0.67Ca0.33MnO3(30 nm)/NdGaO3(001) [LCMO/NGO(001)] films are tuned by inserting an insulating SmFeO3 (SFO) buffer layer at various thicknesses (t). All the layers and the NGO substrates have the same Pbnm symmetry with the octahedra tilting about the b-axis, but different orthorhombicity (d). We found that as t increases, the fully stra...
Tuning of the hole spin relaxation time in single self-assembled In1−xGaxAs/GaAs quantum dots by electric field
We investigate the electric field tuning of the phonon-assisted hole spin relaxation in single self-assembled In1−xGaxAs/GaAs quantum dots(QDs), using an atomistic empirical pseudopotential method. We find that the electric field along the growth direction can tune the hole spin relaxation time for more than one order of magnitude. The electric field can prolong or shorten the hole spin lifet...

Thermoelectric transport properties of diamond-like Cu1−xFe1+xS2 tetrahedral compounds
Polycrystalline samples with the composition of Cu1−xFe1+xS2 (x = 0, 0.01, 0.03, 0.05, 0.1) were synthesized by a melting-annealing-sintering process. X-ray powder diffraction reveals all the samples are phase pure. The backscattered electron image and X-ray map indicate that all elements are distributed homogeneously in the matrix. The measurements of Hall coefficient, electrical conduct...
Heat generation in an elastic binder system with embedded discrete energetic particles due to high-frequency, periodic mechanical excitation
High-frequency mechanical excitation can induce heating within energetic materials and may lead to advances in explosives detection and defeat. In order to examine the nature of this mechanically induced heating, samples of an elastic binder (Sylgard 184) were embedded with inert and energetic particles placed in a fixed spatial pattern and were subsequently excited with an ultrasonic transduce...

Understanding the early cycling evolution behaviors for phase change memory application
The RESET current of T-shaped phase change memory cells with 35 nm heating electrodes has been studied to understand the behavior of early cycling evolution. show that the RESET current has been significantly reduced after the early cycling evolution (1st RESET) operation. Compared the transmission electron microscope images, it is found that the hexagonal Ge2Sb2Te5 (GST) crystal grains are c...
Field dependence of the magnetic structure of TbMn2O5
The evolution of the magnetic propagation vector of the magnetically ordered phases of TbMn2O5 has been studied as a function of magnetic field applied parallel to both [010] and [100] axes. The results have been used to construct (H, T) phase diagrams showing the regions of stability of the three distinct phases IC1, C, and IC2 known to exist in zero field. Application of magnetic field along ...

Expanded graphite—Phenolic resin composites based double layer microwave absorber for X-band applications
In this investigation, double layermicrowave absorbers are designed and developed with paired combination of 5 wt. %, 7 wt. %, 8 wt. %, and 10 wt. % expanded graphite-novolac phenolic resin (EG-NPR) composites, in the frequency range of 8.2–12.4 GHz. The thickness and compositional combination of the two layers constituting the absorber are optimized to achieve minimum value of reflec...
Femtosecond laser induced periodic surface structures on multi-layer graphene
In this work, we present an observation of laser induced periodic surface structures (LIPSS) on graphene. LIPSS on other materials have been observed for nearly 50 years, but until now, not on graphene. Our findings for LIPSS on multi-layergraphene were consistent with previous reports of LIPSS on other materials, thus classifying them as high spatial frequency LIPSS. LIPSS on multi-layergraphe...
Analysis of shockless dynamic compression data on solids to multi-megabar pressures: Application to tantalum
Magnetically-driven, planar shockless-compression experiments to multi-megabar pressures were performed on tantalum samples using a stripline target geometry. Free-surface velocity waveforms were measured in 15 cases; nine of these in a dual-sample configuration with two samples of different thicknesses on opposing electrodes, and six in a single-sample configuration with a bare electrode oppos...
Size-dependent elastic properties of oxidized silicon nanorods
In this work, we have simulated a three point bending test for Si nanorods of different sizes with an oxide coating of different thicknesses using molecular dynamics simulations and the finite element modeling (FEM). We tested nanorods with diameters from 6 to 16 nm, which had lengths from 31 to 62 nm. Our aim was to estimate how well the elastic properties of Si nanorods can be described u...