Publisher's Note: “Computational prediction of probabilistic ignition threshold of pressed granular Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) under shock loading” [J. Appl. Phys. 120, 115902 (2016)]
(Source: Journal of Applied Physics)
Source: Journal of Applied Physics - November 14, 2016 Category: Physics Authors: Seokpum Kim, Christopher Miller, Yasuyuki Horie, Christopher Molek, Eric Welle and Min Zhou Source Type: research
Hydrogen induced mobility enhancement in RF sputtered Cu2O thin films
PolycrystallineCu2Othin films were prepared on c-sapphire substrates by reactive radio-frequencysputtering at various temperatures between 500 and 925 K employing a metallic target and utilizing an argon/hydrogen/oxygen gas mixture. It is demonstrated that the use of hydrogen in thesputter deposition process beneficially affects the transport properties of theCu2Ofilms obtained. Correlating the amount of hydrogen incorporated into thethin films, thefilm morphology and the transport and luminescence properties demonstrate that in this approach hydrogen is predominantly accumulated at thegrain boundaries of the polycrysta...
Source: Journal of Applied Physics - November 14, 2016 Category: Physics Authors: K. P. Hering, C. Kandzia, J. Benz, B. G. Kramm, M. Eickhoff and P. J. Klar Source Type: research
Point defect reduction in wide bandgap semiconductors by defect quasi Fermi level control
A theoretical framework for a general approach to reducepoint defect density in materials via control of defect quasiFermi level (dQFL) is presented. The control of dQFL is achieved via excess minority carrier generation. General guidelines for controlling dQFL that lead to a significant reduction in compensatingpoint defects in anydoped material is proposed. The framework introduces and incorporates the effects of various factors that control the efficacy of the defect reduction process such as defect level, defect formation energy,bandgap, and excess minoritycarrier density. Modified formation energy diagrams are propose...
Source: Journal of Applied Physics - November 14, 2016 Category: Physics Authors: P. Reddy, M. P. Hoffmann, F. Kaess, Z. Bryan, I. Bryan, M. Bobea, A. Klump, J. Tweedie, R. Kirste, S. Mita, M. Gerhold, R. Collazo and Z. Sitar Source Type: research
Impact of contact couplings on thermoelectric properties of anti, Fano, and Breit-Wigner resonant junctions
Quantum interference is a well-known phenomenon which results in unique features of the transmission spectra of molecular junctions at the nanoscale. We investigate and compare thethermoelectricproperties of three types of junctions like the anti, Breit-Wigner, and Fanoresonances. Due to its asymmetric line-shaped transmission function, Fanoresonances lead to a largerthermoelectric figure of merit (ZT) than the symmetric anti and Breit-Wignerresonances. The occurrence ofquantum interference in molecular and other nanoscale junctions is independent of contact couplings between the sandwiched molecules and left/rightelectrod...
Source: Journal of Applied Physics - November 14, 2016 Category: Physics Authors: Rui-Ning Wang, Guo-Yi Dong, Shu-Fang Wang, Guang-Sheng Fu and Jiang-Long Wang Source Type: research
Real-space phase field investigation of evolving magnetic domains and twin structures in a ferromagnetic shape memory alloy
A real-space phase field model combining Landau –Lifshitz–Gilbertequation and time-dependent Ginzburg –Landauequation is developed to investigate the evolution offerromagnetic domains and martensitic twinstructures in aferromagneticshape memoryalloy at different lengthscales. Both domain and twinstructures are obtained by simultaneously solving for minimization of magnetic,elastic, and magnetoelastic coupling energy terms via a nonlinear finite element method. The model is applied to simulate magneto-structural evolution within ananoparticle and a bulk single-crystal of thealloy Ni2MnGa, which are subjected to mechan...
Source: Journal of Applied Physics - November 14, 2016 Category: Physics Authors: H. H. Wu, A. Pramanick, Y. B. Ke and X.-L. Wang Source Type: research
Exchange bias in nano-ferrihydrite
We report the results of investigations of the effect of cooling in an externalmagnetic field starting from the temperature over superparamagnetic blocking temperature TB on the shift ofmagnetic hysteresis loops in systems of ferrihydritenanoparticles from ∼2.5 to ∼5 nm in size with different TB values. In virtue of highanisotropy fields of ferrihydritenanoparticles and openhysteresis loops in the range of experimentally attainablemagnetic fields, the shape ofhysteresis loops of such objects in the field-cooling mode is influenced by the minorhysteresis loop effect. A technique is proposed for distinguishing theexcha...
Source: Journal of Applied Physics - November 14, 2016 Category: Physics Authors: D. A. Balaev, A. A. Krasikov, A. A. Dubrovskiy, S. I. Popkov, S. V. Stolyar, R. S. Iskhakov, V. P. Ladygina and R. N. Yaroslavtsev Source Type: research
Exchange stiffness in ultrathin perpendicularly magnetized CoFeB layers determined using the spectroscopy of electrically excited spin waves
Wemeasure the frequencies ofspin waves in nm-thick perpendicularly magnetized FeCoB systems, and model the frequencies to deduce the exchange stiffness of thismaterial in the ultrathin limit. For this, we embody the layers inmagnetic tunnel junctions patterned into circularnanopillars of diameters ranging from 100 to 300 nm, and we use magneto-resistance to determine which rf-current frequencies are efficient in populating thespin wave modes. Micromagnetic calculations indicate that the ultrathin nature of the layer and the largewave vectors used ensure that thespin wave frequencies are predominantly determined by the e...
Source: Journal of Applied Physics - November 14, 2016 Category: Physics Authors: T. Devolder, J.-V. Kim, L. Nistor, R. Sousa, B. Rodmacq and B. Di ény Source Type: research
Perturbation and coupling of microcavity plasmas through charge injected into an intervening microchannel
Coupling between twomicrocavityplasmas in a symmetric, microfabricateddielectric barrier structure has been observed by injectingcharge from one of theplasmas into an intervening microchannel. Periodic modulation of theelectric field strength in the injector (or electron “donor”) cavity has the effect of deforming the acceptor microplasma which exhibits two distinct and stable spatiotemporal modes. Throughout the time interval in which the two microplasmas are coupled electrostatically, the acceptorplasma is elongated and displaced by 75 –100 μm ( ∼30% of its diameter) in the direction of the microchannel. The d...
Source: Journal of Applied Physics - November 14, 2016 Category: Physics Authors: Y. Wang, J. H. Ni, S. Zhong, S. Cai, X. Zhang, C. Liu, S.-J. Park and J. G. Eden Source Type: research
Perspective: Interface generation of spin-orbit torques
Most of the modern spintronics developments rely on the manipulation of magnetization states via electric currents, which started with the discovery ofspin transfertorque effects 20 years ago. By now, it has been realized thatspin-orbit coupling provides a particularly efficient pathway for generating spin torques fromcharge currents. At the same time,spin-orbit effects can be enhanced at interfaces, which opens up novel device concepts. Here, we discuss two examples of such interfacial spin-orbit torques, namely, systems with inherently two-dimensionalmaterials and metallic bilayers with strong Rashbaspin-orbit coupling a...
Source: Journal of Applied Physics - November 14, 2016 Category: Physics Authors: Joseph Sklenar, Wei Zhang, Matthias B. Jungfleisch, Wanjun Jiang, Hilal Saglam, John E. Pearson, John B. Ketterson and Axel Hoffmann Source Type: research
On the interplay between Si(110) epilayer atomic roughness and subsequent 3C-SiC growth direction
In this contribution, we performed thegrowth of a 3C-SiC/Si/3C-SiC layer stack on a Si(001) substrate by means of chemical vapor deposition. We show that, by tuning thegrowth conditions, the 3C-SiC epilayer can begrown along either the [111] direction or the [110] direction. The key parameter for thegrowth of the desired 3C-SiC orientation on the Si(110)/3C-SiC(001)/Si(001)heterostructure is highlighted and is linked to the Si epilayer surface morphology. Theepitaxial relation between the layers has been identified usingX-ray diffraction andtransmission electron microscopy(TEM). We showed that, regardless of the top 3C-SiC...
Source: Journal of Applied Physics - November 11, 2016 Category: Physics Authors: Rami Khazaka, Jean-Fran çois Michaud, Philippe Vennéguès, Luan Nguyen, Daniel Alquier and Marc Portail Source Type: research
Theoretical study of the reaction kinetics and the detonation wave profile for 1,3,5-triamino-2,4,6-trinitrobenzene
We simulate thereaction process of 1,3,5-triamino-2,4,6-trinitrobenzene in wide temperature and pressure ranges by molecular dynamics and evaluate the intermediate molecules, chemicalreaction rates, and Hugoniot relations. Based on them, the leading shock wave, fastreaction zone, Chapman-Jouguet state, and slowreaction zone under detonation are investigated by different theoretical methods. A complete structure of thedetonation wave is obtained. The calculated detonation velocity, detonation pressure, detonation products, and the length of thereaction zone are in agreement with the experiments and others' calculations. We ...
Source: Journal of Applied Physics - November 11, 2016 Category: Physics Authors: Yao Long and Jun Chen Source Type: research
Inverted organic light-emitting diodes with an electrochemically deposited zinc oxide electron injection layer
Electrical and optical properties of poly(dioctylfluorene-alt-benzothiadiazole) based invertedorganic light-emitting diodes (iOLEDs) with electrochemicallydepositedZnO electron-injecting layer (EIL) have been studied. The device characteristics of the iOLEDs fabricated in this work (8600 cd/m2, 1.5 cd/A at 6.0 V) are almost comparable to those of conventional iOLEDs withsputteredZnO EIL, indicating that the electron injection properties ofelectrodepositedZnO EIL are similar to those ofsputteredZnO EIL. Impedance spectroscopy reveals that the equivalent circuits of iOLEDs with electrochemicallydepositedZnO EIL and w...
Source: Journal of Applied Physics - November 11, 2016 Category: Physics Authors: Makoto Takada, Suguru Furuta, Takashi Kobayashi, Takashi Nagase, Tsutomu Shinagawa, Masanobu Izaki and Hiroyoshi Naito Source Type: research
Surface effects on nitrogen vacancy centers neutralization in diamond
The performance of nitrogen vacancy (NV−) based magnetic sensors strongly depends on the stability of nitrogen vacancy centers near thediamond surface. The sensitivity ofmagnetic field detection is diminished as the NV− turns into the neutralized charge state NV0. We investigate the neutralization of NV− and calculate the ratio of NV0 to total NV (NV−+NV0) caused by a hydrogen terminateddiamond with asurface water layer. We find that NV− neutralization exhibits two distinct regions: near the surface, where the NV− is completely neutralized, and in the bulk, where the neutralization ratio is inversely proportion...
Source: Journal of Applied Physics - November 11, 2016 Category: Physics Authors: Arthur N. Newell, Dontray A. Dowdell and D. H. Santamore Source Type: research
Near perfect ultrasonic omnidirectional transducer using the optimal patterning of the zero-index acoustic metamaterials
This study proposes the theoretical optimalpatterning method based on the geometrical transformation acoustics to design anultrasonic omnidirectionaltransducer system, which is composed of the designed near zero-index acousticmetamaterial (ZIAMM). The designed ZIAMM is made of circular rubber rods in water matrix. Meanwhile, the curved unit cell structure is necessary to arrange the designed ZIAMM effectively into the circular-shapedultrasonic omnidirectionaltransducer system. To this end, we transform the square unit cell into the curved unit cell in the physical space, instead of starting from a homogeneous medium. Also ...
Source: Journal of Applied Physics - November 11, 2016 Category: Physics Authors: Jaeyub Hyun and Semyung Wang Source Type: research
Local and average structures of BaTiO3-Bi(Zn1/2Ti1/2)O3
The complex crystallographicstructures of (1 −x)BaTiO3-xBi(Zn1/2Ti1/2)O3 (BT-xBZT) are examined using high resolution synchrotronX-ray diffraction,neutron diffraction, andneutron pair distribution function (PDF) analyses. The short-rangestructures are characterized from the PDFs, and a combined analysis of the X-ray andneutrondiffraction patterns is used to determine the long-rangestructures. The results demonstrate that thestructure appears different when averaged over different length scales. In all compositions, the localstructures determined from the PDFs show local tetragonal distortions (i.e.,c/a > 1). However,...
Source: Journal of Applied Physics - November 11, 2016 Category: Physics Authors: Tedi-Marie Usher, Thanakorn Iamsasri, Jennifer S. Forrester, Natthaphon Raengthon, Narit Triamnak, David P. Cann and Jacob L. Jones Source Type: research
