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We investigate subwavelength grating-coupled distributed Bragg reflector (DBR) in order to achieve total absorption at preselected wavelengths in a graphene monolayer. Multispectral and near-unity absorption (approximately 99.44% of the incident light at normal incidence) can be achieved in the proposed photonic structure at near-infrared (NIR) regimes. When the system meets the condition of critical coupling, the excited guided mode resonance (GMR) occurs at the resonance wavelength, and the corresponding electric field intensity around the graphene sheet can be greatly enhanced due to the reinforced light-graphene interaction. Multiple absorption peaks can be tuned within the wavelength region of 1.3 μm to 1.6 μm by varying the structural parameters. Our findings also indicate that the near-total-absorption peaks are highly dependent on the number and thickness of unit cells in DBR. These features make the proposed structure have great potential in applications of scalable perfect absorbers (PAs). [ABSTRACT FROM AUTHOR]

In this paper, moiré and emission tomography are integrated to visualize and diagnose the arc plasma jet flowing into air, and the argon arc plasma jet is chosen as a practical example for experiment. The refractive index distribution and structure of the measured flow field are simultaneously obtained by moiré and emission tomography respectively. As a result, the mixed flow field—arc plasma jet flowing into air can be divided into two regions. Finally, the different reconstruction models are adopted to obtain the temperature and electron number density distributions for the two different regions. [ABSTRACT FROM AUTHOR]

Abstract: Light trapping structures with top subwavelength dielectric gratings and back metallic triangle substrate attached to amorphous Si (a-Si) thin film solar cells (TFSCs) are studied. As a result of the grating diffraction effect and surface-plasmon polaritons on substrate, obvious optical absorption enhancement can be achieved in broad wavelength range especially for transverse magnetic (TM) polarized light. Rigorous coupled-wave analysis (RCWA) numerical calculation shows that, compared with bare a-Si TFSCs, the average enhancement is above 20% in the presupposed wavelength range from 0.3 to 1.1μm as the incident angle varies from 0° to 60°, and 30% more absorption would be increased when the incident light is TM only. [Copyright &y& Elsevier]

Abstract: In this paper, arc plasma’s electron number density diagnosis by measuring its refractive index distribution is studied, while both the indirect and direct methods are discussed. As a result of the temperature imprecision will be carried into the reconstruction of the electron number density distribution in the indirect methods, the direct methods are preferred and schemed. For the direct methods, two reconstruction models which can directly obtain the electron number density distribution are compared, meanwhile, the unity and diversity of them are proposed. Besides, the involved electron number density reconstruction imprecision is analyzed. In short, this study will provide some reference on arc plasma’s electron number density diagnosis by the optical methods which are based on the measurement of the refractive index. [Copyright &y& Elsevier]

Abstract: Aiming at the effect of species composition distribution on flow field''s temperature reconstruction from the experimentally measured refractive index, a temperature partition reconstruction method based on flow field''s phase distribution is proposed. Moiré deflection tomography is chosen to obtain the refractive index of a flame with probe wavelength of 808nm. Enlightened by the visual characteristic of optical computerized tomography (OCT) for flow field and the practical structure of the flame, it is divided into three regions in radial direction based on its phase distribution. The essence is that the temperature is reconstructed with adopting different species composition for different regions. Finally, the rationality of the method is analyzed. [Copyright &y& Elsevier]

A growth diagram of Lu-Fe-0 compounds on MgO (111) substrates using pulsed laser deposition is constructed based on extensive growth experiments. The LuFe204 phase can only be grown in a small range of temperature and O2 pressure conditions. An understanding of the growth mechanism of Lu-Fe-0 compound films is offered in terms of the thermochemistry at the surface. Superparamagnetism is observed in the LuFe204 film and is explained in terms of the effect of the impurity hexagonal LuFeCO3 (h-LuFe03) phase and structural defects. [ABSTRACT FROM AUTHOR]

Abstract: A novel plasmonic nanolens formed by a tapered subwavelength metal slit surrounded by surface dielectric gratings is proposed and demonstrated numerically. By patterning surface corrugations on the output surface, the beam can be focused, by regulating the aperture, the focal length can be controlled effectively. Numerical simulations using Finite-Difference Time-Domain (FDTD) method coupled with anisotropic perfectly matched layer (APML) boundary conditions verify that the proposed metallic lens can focus the radiation on the scale of a wavelength below the substrate and the method is effective for the design of nano-optical devices such as optical microprobes. [Copyright &y& Elsevier]

Abstract: Objective: To screen and clone multi-drug resistance (MDR) related genes in MDR acute myeloid leukemia cells (HL-60/MDR). Methods: HL-60/MDR was established using All-Trans Retinoic Acid. With the HL-60 cells as “tester” and HL60/MDR as “driver”, the cDNA library of HL-60/MDR was established by suppression subtractive hybridization. Then 12 of the resulting subtracted cDNA clones were selected for DNA sequencing and homology analysis. The obtained expressed sequence tags (ESTs) were analyzed with the GenBank BLASTN program to identify sequence homologies to known genes. Results: The HL-60/MDR cells had different multi-drug resistance to six kinds of chemotherapeutic drugs. The 211 positive gene clones in differential cDNA library of HL-60/MDR cells were amplified with PCR and 46 gene clones exhibited differential expression (ratio >3). Twelve gene clones with significant differential expression (ratio >5) were screened out to homology analysis. Of these, 11 matched known genes and the rest 1 showed no significant homology to human or non-human known sequences. It was named as gene clone HA117. Conclusions: This effort provides the partial list of genes differential expressed in HL-60/MDR cells and a novel gene HA117 was found to be related to MDR. Identification of these genes contributes to our understanding of MDR development, and potentially provides candidate target genes to overcome MDR. [Copyright &y& Elsevier]

Enlightened by the wide application of optical computerized tomography (OCT) in various flow fields’ visualization and parameter measurement, the potential feasibility of it on measuring gas jet flow velocity is discussed in this paper. The dependence of flow velocity on flow field's refractive index and dynamic pressure is deduced initially. An argon gas jet flow is chosen as an example for experiment, and the refractive index measurement is achieved by moiré tomography, while the dynamic pressure is obtained by a pressure sensor. In a word, both the theoretical and experimental results prove that OCT could be feasible to obtain the flow velocity of gas jet flows. [ABSTRACT FROM AUTHOR]

The structure of a one-dimensional photonic crystal (1D-PhC) with a graphene-based defect is proposed and investigated to enhance the optical response of graphene in the visible to near-infrared (NIR) wavelength region. An electro-optical (EO) tuning material lithium niobate (LiNbO, LN) is selected as the spacer layer with an external voltage applied on it. By means of the transfer-matrix method (TMM), the dependence of the absorption characteristics on the incident angle and period numbers is analyzed. The possibility of the resonant wavelength being tunable via the external voltage and thickness of the LN layer is also discussed. It is shown that nearly perfect absorption can be achieved by a certain choice of the period numbers of the 1D-PhC surrounding the defect layer at a specific incidence. The linear relation between the peak wavelength and the applied external voltage is also demonstrated, and it is possible to control the position and number of the resonant wavelengths by varying the voltage and thickness of the LN defect layer. [ABSTRACT FROM AUTHOR]

We design an effective light trapping scheme through engineering metallic gratings and one-dimensional dielectric photonic crystals (PhCs) to increase the optical path length of light within the solar cells. This incorporation can result in broadband optical absorption enhancement not only for transverse magnetic polarized light but also for transverse-electric polarization. Even when no plasmonic mode can be excited, due to the high reflection of the PhCs, the absorption in the active region can still be enhanced. Rigorous coupled wave analysis results demonstrate that such a hybrid structure boosts the overall cell performance by increasing the light trapping capabilities and is especially effective at the silicon band edge. This kind of design can be used to increase the optical absorption over a wide spectral range and is relatively independent of the angle of incidence. [ABSTRACT FROM AUTHOR]

We have studied the origin of the exchange bias effect in the Au-Fe3O4 dumbbell nanoparticles in two samples with different sizes of the Au seed nanoparticles (4.1 and 2.7 nm) and same size of Fe3O4 nanoparticles (9.8 nm). The magnetization, small-angle neutron-scattering, synchrotron x-ray diffraction, and scanning transmission electron microscope measurements determined the antiferromagnetic FeO wüstite phase within Fe3O4 nanoparticles, originating at the interface with the Au nanoparticles. The interface between antiferromagnetic FeO and ferrimagnetic Fe3O4 is giving rise to the exchange bias effect. The strength of the exchange bias fields depends on the interfacial area and lattice mismatch between both phases. We propose that the charge transfer from the Au nanoparticles is responsible for a partial reduction of the Fe3O4 into the FeO phase at the interface with Au nanoparticles. The Au-O bonds are formed, presumably across the interface to accommodate an excess of oxygen released during the reduction of magnetite. [ABSTRACT FROM AUTHOR]

Abstract: An argon arc jet plasma flowing into air is chosen as a practical example to study the multiple species jet plasma's optical computerized tomography (OCT) diagnosis. The refractive index models of the pure argon and the multiple species arc plasmas are supplied. On the basis of which, the temperature reconstruction model of the multiple species arc plasma is further derived. By theoretical calculation, the effect of mixed air on the refractive index is given. For the sake of better proving the effect of directly omitting the mixed air on flow field's temperature reconstruction from the refractive index, a simulated experiment is supplied. Finally, the condition, which can be adopted to estimate that whether the pure argon arc plasma refractive index model still can be used as the temperature reconstruction model of the argon arc plasma jet flowing into air, is proposed. [Copyright &y& Elsevier]

Studies of magnetic domain and magnetic anisotropy in collected nanoparticles are crucial for both understanding interparticle interaction and engineering in applications. In order to characterize the microscopic surface morphology and the nanoscale magnetic domain structure of Fe nanoparticles, a scanning tunneling microscope and a scanning electron microscope with polarization analysis (SEMPA) were used in our experiment. For the coverage of 9–13 monolayers (MLs) Fe deposited on Al2O3/NiAl(100), circular and well-separated nanoparticles were grown. As the coverage increased up to 23–33 ML, these Fe nanoparticles started to coalesce and form elongated islands. Therefore a transition from isotropic to anisotropic in-plane magnetism was observed. Our proposed uniaxial magnetic anisotropy models effectively explain the azimuthal angle dependent two-step hysteresis loops. Moreover, the in situ measured SEMPA images clearly show the coverage dependent evolution of magnetic domain structure. Variations in interparticle interaction and magnetic correlation length with increasing Fe coverage are also reported. [ABSTRACT FROM AUTHOR]

Characterization of the onset of a phase transition is often challenging due to the fluctuations of the correlation length scales of the order parameters. This is especially true for second-order structuralphase transition due to minute changes involved in the relevant lattice constants. A classic example is the cubic-to-tetragonal secondorder phase transition in SrTiO3 (STO), which is so subtle that it is still unresolved. Here, we demonstrate an approach to resolve this issue by epitaxially grown rhombohedral La0.7Sr0.3MnO3 (LSMO) thin films on the cubic STO (100) substrate. The shear strain induced nanotwinning waves in the LSMO film are extremely sensitive to the cubic-totetragonal structural-phase transitions of the STO substrate. Upon cooling from room temperature, the development of the nanotwinning waves is spatially inhomogeneous. Untwinned, atomically flat domains, ranging in size from 100 to 300 nm, start to appear randomly in the twinned phase between 265 and 175 K. At ~139 K, the untwinned, atomically flat domains start to grow rapidly into micrometer scale and finally become dominant at ~108 K. These results indicate that the low-temperature tetragonal precursor phase of STO has already nucleated at 265 K, significantly higher than the critical temperature of STO (~105 K). Our work paves a pathway to visualize the onset stages of structural-phase transitions that are too subtle to be observed using direct-imaging methods. [ABSTRACT FROM AUTHOR]

Thin flakes of Cr1/3NbS2 are fabricated successfully via microexfoliation techniques. Temperature-dependent and field-dependent magnetizations of thin flakes with various thicknesses are investigated. When the thickness of the flake is around several hundred nanometers, the softening and eventual disappearance of the bulk soliton peak is accompanied by the appearance of other magnetic peaks at lower magnetic fields. The emergence and annihilation of the soliton peaks are explained and simulated theoretically by the change in spin spiral number inside the soliton lattice due to dimensional confinement. Compared to the conventional magnetic states in nanoscale materials, the stability and thickness tunability of quantified spin spirals make Cr1/3NbS2 a potential candidate for spintronics nanodevices beyond Moore's law. [ABSTRACT FROM AUTHOR]

Combined scanning tunneling microscopy, spectroscopy, and local barrier height (LBH) studies show that low-temperature-cleaved optimally doped Ba(Fe1-xCox)2As2 crystals with x = 0.06, with Tc = 22 K, have complicated morphologies. Although the cleavage surface and hence the morphologies are variable, the superconducting gap maps show the same gap widths and nanometer size inhomogeneities irrelevant to the morphology. Based on the spectroscopy and LBH maps, the bright patches and dark stripes in the morphologies are identified as Ba- and As-dominated surface terminations, respectively. Magnetic impurities, possibly due to Co or Fe atoms, are believed to create local in-gap state and, in addition, suppress the superconducting coherence peaks. This study will clarify the confusion on the cleavage surface terminations of the Fe-based superconductors and its relation with the electronic structures. [ABSTRACT FROM AUTHOR]

Discusses the synthesis of a one-dimensional ferromagnetic cobalt platinum alloy nanowires. Decomposition of platinum acetylatocetonate and cobalt carbonyl in ethylenediamine solvent through a solvothermal reaction. Role of solvent choice in morphology synthesis; Analysis of nanowire growth in solvothermal conditions through scanning electron microscope imaging.

We report on the use of helium ion implantation to independently control the out-of-plane lattice constant in epitaxial La0.7Sr0.3MnO3 thin films without changing the in-plane lattice constants. The process is reversible by a vacuum anneal. Resistance and magnetization measurements show that even a small increase in the out-of-plane lattice constant of less than 1% can shift the metal-insulator transition and Curie temperatures by more than 100 °C. Unlike conventional epitaxy-based strain tuning methods which are constrained not only by the Poisson effect but by the limited set of available substrates, the present study shows that strain can be independently and continuously controlled along a single axis. This permits novel control over orbital populations through Jahn-Teller effects, as shown by Monte Carlo simulations on a double-exchange model. The ability to reversibly control a single lattice parameter substantially broadens the phase space for experimental exploration of predictive models and leads to new possibilities for control over materials' functional properties. [ABSTRACT FROM AUTHOR]

A metastable phase α-FeSi2 was epitaxially stabilized on a silicon substrate using pulsed laser deposition. Nonmetallic and ferromagnetic behaviors are tailored on α-FeSi2 (111) thin films, while the bulk material of α-FeSi2 is metallic and nonmagnetic. The transport property of the films renders two different conducting states with a strong crossover at 50 K, which is accompanied by the onset of a ferromagnetic transition as well as a substantial magnetoresistance. These experimental results are discussed in terms of the unusual electronic structure of α-FeSi2 obtained within density functional calculations and Boltzmann transport calculations with and without strain. Our finding sheds light on achieving ferromagnetic semiconductors through both their structure and doping tailoring, and provides an example of a tailored material with rich functionalities for both basic research and practical applications. [ABSTRACT FROM AUTHOR]

Particularly in Sr2IrO4, the interplay between spin-orbit coupling, bandwidth and on-site Coulomb repulsion stabilizes a Jeff = 1/2 spin-orbital entangled insulating state at low temperatures. Whether this insulating phase is Mott- or Slater-type, has been under intense debate. We address this issue via spatially resolved imaging and spectroscopic studies of the Sr2IrO4 surface using scanning tunneling microscopy/ spectroscopy (STM/S). STS results clearly illustrate the opening of an insulating gap (150 ∼ 250 meV) below the Néel temperature (TN), in qualitative agreement with our density-functional theory (DFT) calculations. More importantly, the temperature dependence of the gap is qualitatively consistent with our DFT 1 dynamical mean field theory (DMFT) results, both showing a continuous transition from a gapped insulating ground state to a non-gap phase as temperatures approach TN. These results indicate a significant Slater character of gap formation, thus suggesting that Sr2IrO4 is a uniquely correlated system, where Slater and Mott-Hubbard-type behaviors coexist. [ABSTRACT FROM AUTHOR]

Traditionally, magneto-dielectric effects have been developed by combining ferroelectric and magnetic materials. Here, we show a magneto-dielectric effect from optically-generated intermolecular charge-transfer states in an organic semiconducting donor:acceptor (PVK:TCNB) system. We observe in magnetic field effects of photoluminescence that a magnetic field can change singlet/triplet population ratio in intermolecular charge-transfer states. Furthermore, our theoretical analysis and experimental evidence indicate that the singlets and triplets in charge-transfer states have stronger and weaker electrical polarizations, respectively. Therefore, the observed magneto-dielectric effect can be attributed to magnetically-dependent singlet/triplet ratio in intermolecular charge-transfer states. In principle, a magneto-dielectric effect can be generated through two different channels based on magneto-polarization and magneto-current effects when the singlet/triplet ratio in intermolecular charge-transfer states is changed by a magnetic field. We find, from the simulation of dielectric effects, that magneto-polarization and magneto-current effects play primary and secondary roles in the generation of magneto-dielectric effect. [ABSTRACT FROM AUTHOR]

The crystal and magnetic structures of single-crystalline hexagonal LuFeO3 films have been studied using x-ray, electron, and neutron diffraction methods. The polar structure of these films are found to persist up to 1050 K; and the switchability of the polar behavior is observed at room temperature, indicating ferroelectricity. An antiferromagnetic order was shown to occur below 440 K, followed by a spin reorientation resulting in a weak ferromagnetic order below 130 K. This observation of coexisting multiple ferroic orders demonstrates that hexagonal LuFeO3 films are room-temperature multiferroics. [ABSTRACT FROM AUTHOR]

We study experimentally and theoretically the electronic and magnetic properties of two insulating double perovskites that show similar atomic and electronic structure but different magnetic properties. In magnetization measurements, La2ZnIrO6 displays weak ferromagnetic behavior below 7.5 K, whereas La2MgIrO6 shows antiferromagnetic behavior below. TN =12 K. Electronic structure calculations find that the weak ferromagnetic behavior observed in La2ZnIrO6 is in fact due to canted antiferromagnetism. The calculations also predict canted antiferromagnetic behavior in La2MgIrO6, but intriguingly, this was not observed. Neutron diffraction measurements confirm the essentially antiferromagnetic behavior of both systems but lack the sensitivity to resolve the small (O.22pB/Ir) ferromagnetic component in La2ZnIrO6. Overall, the results presented here indicate the crucial role of spin-orbit coupling (SOC) and the on-site Coulomb repulsion on the magnetic, transport, and thermodynamic properties of both compounds. The electronic structure calculations show that both compounds, like Sr2IrO4, are Jeff = 1/2 Mott insulators. Our present findings suggest that La2ZnIrO6 and La2MgIrO6 provide a new playground to study the interplay between SOC and on-site Coulomb repulsion in a Sd transition-metal oxide. [ABSTRACT FROM AUTHOR]

We report a comprehensive study of dc susceptibility, specific-heat, neutron-diffraction, and inelastic neutron-scattering measurements on polycrystalline Ba3(Cr1-xVx)2O8 samples, where x=0, 0.06, 0.15, and 0.53. A Jahn-Teller structure transition occurs for x=0, 0.06, and 0.15 samples, and the transition temperature is reduced upon vanadium substitution from 70(2) K at x=0 to 60(2) K at x=0.06 and 0.15. The structure becomes less distorted as x increases, and such transition disappears at x=0.53. The observed magnetic excitation spectrum indicates that the singlet ground state remains unaltered and spin-gap energy Δ=1.3(1) meV is identical within the instrument resolution for all x. In addition, the dispersion bandwidth W decreases with increase of x. At x=0.53, W is reduced to 1.4(1) meV from 2.0(1) meV at x=0. [ABSTRACT FROM AUTHOR]

A one-step synthesis of L10FePt nanoparticles ca. 17.0 nm in diameter by reductive decomposition of the single-source precursor, FePt(CO)4dppmBr2, on a water-soluble support (Na2CO3) is demonstrated. Direct conversion of a FePt(CO)4dppmBr2/Na2CO3composite to a L10FePt/Na2CO3nanocomposite occurs at 600 °C under getter gas with metal-ion reduction and minimal nanoparticle coalescence. Triturating the resulting nanocomposite with water simultaneously dissolves the sodium carbonate solid support and precipitates the formed fct FePt nanoparticles. As-prepared FePt nanoparticles are ferromagnetic and exhibit coercivities of 14.5 kOe at 300 K and 21.8 kOe at 5 K. When capped by functionalized methoxypoly(ethylene glycol) surfactant molecules, as-prepared, polydisperse ferromagnetic FePt nanoparticles can be dispersed and size-selected by fractional precipitation. [ABSTRACT FROM AUTHOR]

The authors report the observation of the reversal in the magnetization hysteresis curve of europium sulfide nanocrystals. This phenomenon was investigated through the temperature-dependent magnetization of two classes of nanomaterials, nanocrystalline (2.0 nm<=dNCs<=100 nm) and quantum confined (dNCs<=2.0 nm), where dNCs is the diameter of the nanomaterial. The effect of the size of the nanomaterial on the magnetization is attributed to the competition between the magnetic properties of strained surface atoms and unstrained core atoms. Superconducting quantum interference device probed the magnetic response. Electron microscopy and X-ray diffraction spectroscopy revealed the crystallinity and monodispersivity of the nanomaterials. [ABSTRACT FROM AUTHOR]

Two-dimensional materials such as layered transition-metal dichalcogenides (TMDs) are ideal platforms for studying defect behaviors, an essential step towards defect engineering for novel material functions. Here, we image the 3D lattice locations of selenium-vacancy VSe defects and manipulate them using a scanning tunneling microscope (STM) near the surface of PdSe2, a recently discovered pentagonal layered TMD. The VSe show a characterisitc charging ring in a spatially resolved conductance map, based on which we can determine its subsurface lattice location precisely. Using the STM tip, not only can we reversibly switch the defect states between charge neutral and charge negative, but also trigger migrations of VSe defects. This allows a demonstration of direct "writing" and "erasing" of atomic defects and tracing the diffusion pathways. First-principles calculations reveal a small diffusion barrier of VSe in PdSe2, which is much lower than S vacancy in MoS2 or an O vacancy in TiO2. This finding opens an opportunity of defect engineering in PdSe2 for such as controlled phase transformations and resistive-switching memory device application. [ABSTRACT FROM AUTHOR]

The magnetic domains in two-dimensional layered material Fe3GeTe2 are studied by using a variable-temperature scanning tunneling microscope with a magnetic tip after in situ cleaving of single crystals. A stripy domain structure is revealed in a zero-field-cooled sample below the ferromagnetic transition temperature of 205 K, which is replaced by separate double-walled domains and bubble domains when cooling the sample under a magnetic field of a ferromagnetic Ni tip. The Ni tip can further convert the double-walled domain to a bubble domain pattern as well as move the Neel-type chiral bubble in submicrometer distance. The temperature-dependent evolutions of both zero-field-cooled and field-cooled domain structures correlate well with the bulk magnetization from magnetometry measurements. Atomic resolution scanning tunneling images and spectroscopy are acquired to understand the atomic and electronic structures of the material, which are further corroborated by first-principles calculations. [ABSTRACT FROM AUTHOR]

The article offers information about a study that focused on the synthesis of iron-platinum (FePt) nanoparticles exhibiting high room temperature coercivity. This study was done in line with the interest for developing more complete understanding of ferromagnetism and as materials suitable for high-density magnetic storage. Furthermore, obtaining face-centered-tetragonal FePt nanoparticles exhibiting high room-temperature coercivity is desired for high-density magnetic storage.

Ferromagnetic shape memory alloys (FSMAs) have shown great potential as active components in next generation smart devices due to their exceptionally large magnetic-field-induced strains and fast response times. During application of magnetic fields in FSMAs, as is common in several magnetoelastic smart materials, there occurs simultaneous rotation of magnetic moments and reorientation of twin variants, resolving which, although critical for design of new materials and devices, has been difficult to achieve quantitatively with current characterization methods. At the same time, theoretical modeling of these phenomena also faced limitations due to uncertainties in values of physical properties such as magnetocrystalline anisotropy energy (MCA), especially for off-stoichiometric FSMA compositions. Here, in situ polarized neutron diffraction is used to measure directly the extents of both magnetic moments rotation and crystallographic twin-reorientation in an FSMA single crystal during the application of magnetic fields. Additionally, high-resolution neutron scattering measurements and first-principles calculations based on fully relativistic density functional theory are used to determine accurately the MCA for the compositionally disordered alloy of Ni2Mn1.14Ga0.86. The results from these state-of-the-art experiments and calculations are self-consistently described within a phenomenological framework, which provides quantitative insights into the energetics of magnetostructural coupling in FSMAs. Based on the current model, the energy for magnetoelastic twin boundaries propagation for the studied alloy is estimated to be ~150kJ/m³. [ABSTRACT FROM AUTHOR]