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We study the effect of strain on the magnetic properties and magnetization configurations in nanogranular FexGe1-xfilms (x=0.53±0.05) with and without B20 FeGe nanocrystals surrounded by an amorphous structure. Relaxed films on amorphous silicon nitride membranes reveal a disordered skyrmion phase while films near and on top of a rigid substrate favor ferromagnetism and an anisotropic hybridization of Fedlevels and spin-polarized Gespband states. The weakly coupled topological states emerge at room temperature and become more abundant at cryogenic temperatures without showing indications of pinning at defects or confinement to individual grains. These results demonstrate the possibility to control magnetic exchange and topological magnetism by strain and inform magnetoelasticity-mediated voltage control of topological phases in amorphous quantum materials.

The the structural, electronic, and magnetic characteristics of the ZnSeS solid solution with manganese impurity have been evaluated within the DFT using the hybrid exchange-correlation functional PBE0. The structure of this solid solution was determined in two stages. At the first step the internal coordinates of atoms are optimized, and at the second one the lattice parameter relaxation, including reoptimization of internal coordinates, were done. Further, after the introduction of Mn substitution impurity, electronic energy spectra and the electronic DOS were obtained. Significant changes in parameters of the electronic structure and magnetic properties caused by the manganese impurity were found. It was established that the doped solid solution Mn:ZnSeS is a semiconductor for both electron spin polarizations. [ABSTRACT FROM AUTHOR]

In this study, the electronic and magnetic properties of hydrogen-passivated armchair and zigzag GaN nanoribbons are investigated using density-functional theory. We explore that doped TM atom leads to additional levels in the band gap and thus plays an essential role in spin polarization and changes their properties. Depending on its location in the nanoribbon, the character of spin-dependent electronic property of a doped GaN-NR was analyzed. Our calculations show that, regardless of the position of Mn atoms, GaNNTs are stable in ferromagnetic phase. [ABSTRACT FROM AUTHOR]

Solar cells are currently the focus of a great deal of research. The aim is to reduce their cost price. To achieve this, we need to reduce the mass of the materials and increase the conversion efficiency of these solar cells. This has motivated research into the use of thin films such as a-Si, CdTe, CIGS. This increase in efficiency requires optimizing the performance of the photovoltaic parameters. In this modeling and simulation work, we use the SCAPS-1D software to study the effect of the recombination speed of the electrons and holes in the CIGS layer, the effect of the thickness of the layers and the effect of the gap energy of each layer of the material used for this solar cell on the short-circuit current Jsc, the open-circuit voltage Voc, the form factor FF and the electrical efficiency η of the CIGS cell for a Mo/p-CIGS/p-Si/In2S3/i-ZnO/Al-ZnO single-junction structure. In this study, we found that recombination speed affects the efficiency of the photovoltaic cell. The gap energy of the absorber layers influences the cell's efficiency, while the other layers (In2S3, ZnO, Al-ZnO) do not have a great influence on solar cell performance and increasing the thickness of the absorber layer has a major influence on efficiency, increasing it up to a certain limit. The thicknesses of the CIGS, p-Si, In2S3, i-ZnO and Al‑ZnO layers need to be in the order of 0.3µm, 0.8µm, 0.05µm, 0.07µm and 0.1µm respectively to achieve better efficiency (31.42%).

Doping engineering is crucial for both fundamental science and emerging applications. While transition metal (TM) dopants exhibit considerable advantages in the tuning of magnetism and conductivity in bulk Ga2O3, investigations on TM-doped two-dimensional (2D) Ga2O3 are scarce, both theoretically and experimentally. In this study, the detailed variations in impurity levels within 3d TM-doped 2D Ga2O3 systems have been explored via first-principles calculations using the generalized gradient approximation (GGA) +U method. Our results show that the Co impurity tends to incorporate on the tetrahedral GaII site, while the other dopants favor square pyramidal GaI sites in 2D Ga2O3. Moreover, Sc3+, Ti4+, V4+, Cr3+, Mn3+, Fe3+, Co3+, Ni3+, Cu2+, and Zn2+ are the energetically favorable charge states. Importantly, a transition from n-type to p-type conductivity occurs at the threshold Cu element as determined by the defect formation energies and partial density of states (PDOS), which can be ascribed to the shift from electron doping to hole doping with respect to the increase in the atomic number in the 3d TM group. Moreover, the spin configurations in the presence of the square pyramidal and tetrahedral coordinated crystal field effects are investigated in detail, and a transition from high-spin to low-spin arrangement is observed. As the atomic number of the 3d TM dopant increases, the percentage contribution of O ions to the total magnetic moment significantly increases due to the electronegativity effect. Additionally, the formed 3d bands for most TM dopants are located near the Fermi level, which can be of significant benefit to the transformation of the absorbing region from ultraviolet to visible/infrared light. Our results provide theoretical guidance for designing 2D Ga2O3 towards optoelectronic and spintronic applications. [ABSTRACT FROM AUTHOR]

This study presents an unmanned aerial vehicle (UAV)-borne vector magnetometer (MAG) system and proposes a new data-processing technique for modeling the residual magnetic anomalies of three types of landmines: the metallic antitank M15, the metallic antipersonnel M16, and the minimum-metal antitank M19. The burial depth and magnetic moment of these landmines were estimated using the measured and simulated residual magnetic anomalies based on the proposed UAV-borne vector MAG model. Initial in-flight validation showed a strong correlation between the residual magnetic anomaly maps obtained from measurements and simulations. To verify the detection capability in real-world conditions, the UAV-borne MAG system was tested at the Korean Combat Training Center. Both simulations and experiments demonstrated the effectiveness of the proposed data-processing method and UAV-borne MAG model in accurately modeling the residual magnetic anomalies of landmines with metallic components. This approach will facilitate the automated detection of M15, M16, and M19 landmines with high detection rates and enable accurate classification. [ABSTRACT FROM AUTHOR]

Solar cells are currently the focus of a great deal of research. The aim is to reduce their cost price. To achieve this, we need to reduce the mass of the materials and increase the conversion efficiency of these solar cells. This has motivated research into the use of thin films such as a-Si, CdTe, CIGS. This increase in efficiency requires optimizing the performance of the photovoltaic parameters. In this modeling and simulation work, we use the SCAPS-1D software to study the effect of the recombination speed of the electrons and holes in the CIGS layer, the effect of the thickness of the layers and the effect of the gap energy of each layer of the material used for this solar cell on the short-circuit current Jsc, the open-circuit voltage Voc, the form factor FF and the electrical efficiency η of the CIGS cell for a Mo/p-CIGS/p-Si/In2S3/i-ZnO/Al-ZnO single-junction structure. In this study, we found that recombination speed affects the efficiency of the photovoltaic cell. The gap energy of the absorber layers influences the cell's efficiency, while the other layers (In2S3, ZnO, Al-ZnO) do not have a great influence on solar cell performance and increasing the thickness of the absorber layer has a major influence on efficiency, increasing it up to a certain limit. The thicknesses of the CIGS, p-Si, In2S3, i-ZnO and Al-ZnO layers need to be in the order of 0.3µm, 0.8µm, 0.05µm, 0.07µm and 0.1µm respectively to achieve better efficiency (31.42%). [ABSTRACT FROM AUTHOR]

A burnable absorber is a material used in nuclear reactors to manage reactivity and extend operational cycles by absorbing neutrons. Gadolinium oxide (Gd2O3) is a prevalent burnable absorber employed in nuclear reactors. By utilizing density functional theory (DFT) within a first-principles framework, a comprehensive exploration into the physical characteristics of the predicted tetragonal phase of Gd2O3 has been effectively conducted. The investigation encompasses structural, electronic, magnetic, elastic, mechanical, bonding, thermophysical, and optical aspects. Since tetragonal Gd2O3 has not been experimentally synthesized, the stability of the tetragonal phase is confirmed through assessments of its structural, lattice dynamical, thermodynamic, and mechanical attributes. Demonstrating semiconducting behavior, the electronic nature reveals a band gap of 1.241 eV. The density of states (DOS) illustration validates the semiconductor electronic character, and the calculated magnetic moment, determined through up-down spin DOS, is 3.06 μB/f.u. The Poisson’s ratio value reflects the dominance of ionic bonding in Gd2O3, a finding corroborated by bond population analysis. Impressively, the tetragonal Gd2O3 displays elevated lattice thermal conductivity value in comparison to its cubic, monoclinic, and hexagonal counterparts. Furthermore, the determined melting point registers at 1709.31 K. In the realm of optics, an analysis based on frequency dependence reveals that tetragonal Gd2O3 holds promise as a candidate for optoelectronic applications, particularly in the ultraviolet (UV) energy range.

The current state of research on spin-orbit interaction in cofactor-free oxidases and dioxygenases during oxygen activation is considered. The spin activation of triplet oxygen during combustion and respiration is analyzed in comparison with the reactions of flavin-containing enzymes, as well as important cofactor-independent dioxygenases. The mechanism of the triplet-singlet transition in glucose oxidase and a number of dioxygenases, including the RuBisCo oxygenase pathway and chirality-induced spin selectivity, is considered. [ABSTRACT FROM AUTHOR]

In the presented work, we propose a systematic investigation of the electronic and optical properties of MnGa2Se4 by combining the spectroscopic ellipsometry carried out at room temperature in the spectral range of 1–4 eV and density functional theory (DFT) calculations. Ellipsometric measurements were collected at an incidence angle between 60° and 75° with a 5° step. The optical direct gap energies of MnGa2Se4 were estimated from the linear extrapolation of the absorption coefficients that were verified by band structure calculation. DFT calculation of the imaginary part ɛ shows that first critical point occurs at 2.46 eV and represents the direct optical transition at Γ point. The total magnetic moment of compound is 3.38 mB. The major contribution in total magnetic moment is due to 3d state of Mn atoms. [ABSTRACT FROM AUTHOR]

In the presented work, we propose a systematic investigation of the electronic and optical properties of MnGa2Se4 by combining the spectroscopic ellipsometry carried out at room temperature in the spectral range of 1–4 eV and density functional theory (DFT) calculations. Ellipsometric measurements were collected at an incidence angle between 60° and 75° with a 5° step. The optical direct gap energies of MnGa2Se4 were estimated from the linear extrapolation of the absorption coefficients that were verified by band structure calculation. DFT calculation of the imaginary part ɛ shows that first critical point occurs at 2.46 eV and represents the direct optical transition at Γ point. The total magnetic moment of compound is 3.38 mB. The major contribution in total magnetic moment is due to 3d state of Mn atoms. [ABSTRACT FROM AUTHOR]

Device applications in magnetic media, spintronics, oxygen membranes, sensors, etc., are some of the uses of ferrite materials. In this work, we have studied the structural, electronic, magnetic, mechanical, and thermoelectric properties of Cs-based double perovskites Cs2AX6 (A = Ge, Mn; X = Cl, I), using Quantum Espresso with generalized gradient approximation Perdew-Burke-Ernzerhof and Perdew-Burke-Ernzerhof in solids exchange-correlation functionals. The band structure results show that Cs2GeCl6 and Cs2MnCl6 are semiconductors with direct band gaps. However, there are bands crossing observed for Cs2GeI6 from the conduction band minimum to the valence band maximum, indicating the metallic nature of the material. Moreover, Cs2MnI6 has magnetic properties; it exhibits a metallic nature in the spin-up state and a semiconductor nature in the spin-down state, suggesting that it can be used in spintronics applications. The calculated total magnetic moment of Cs2MnCl6 is 3:0μB (for both Perdew-Burke-Ernzerhof and Perdew-Burke-Ernzerhof in solids), while for Cs2MnI6, the calculated total magnetic moments are 3:02μB and 3:06μB, for Perdew-Burke-Ernzerhof and Perdew-Burke-Ernzerhof in solids exchange-correlation functionals, respectively. The results of the mechanical properties calculations show that Cs-based double perovskites Cs2AX6 (A = Ge, Mn; X = Cl, I) are mechanically stable. Cauchy's pressure and Poisson's, Frantsevich's, and Pugh's ratios of the studied materials confirm that Cs2MnCl6 is brittle, while the remaining studied double perovskite materials are ductile. Electrical conductivity, thermal conductivity, Seebeck coefficients, power factor, and figure of merit are the thermoelectric parameters analyzed in this study. Seebeck coefficients, electrical conductivity, and power factor increase with the rise in temperature, and Cs2MnX6 (X = Cl, I) double perovskite materials have higher values of electrical conductivity than Cs2GeX6 (X = Cl, I). All the studied materials have positive type conductivity due to their positive Seebeck coefficient values. [ABSTRACT FROM AUTHOR]

The anomalous magnetic moment of the electron, first calculated by Schwinger, lowers the ground state energy of the electron in a weak magnetic field. It is a function of the field and changes signs for large fields, ensuring the stability of the ground state. This has been shown in the past 50 years in numerous papers. The corresponding corrections to the mass of the electron have also been investigated in strong fields using semiclassical methods. We critically review these developments and point out that the calculation for low-lying excited states raises questions. Also, we calculate the contribution from the tadpole diagram, the relevance of which was observed only quite recently.

The anomalous magnetic moment of the electron, first calculated by Schwinger, lowers the ground state energy of the electron in a weak magnetic field. It is a function of the field and changes signs for large fields, ensuring the stability of the ground state. This has been shown in the past 50 years in numerous papers. The corresponding corrections to the mass of the electron have also been investigated in strong fields using semiclassical methods. We critically review these developments and point out that the calculation for low-lying excited states raises questions. Also, we calculate the contribution from the tadpole diagram, the relevance of which was observed only quite recently. [ABSTRACT FROM AUTHOR]

The interaction between sites A, B and X with passivation molecules is restricted when the conventional passivation strategy is applied in perovskite (ABX3) photovoltaics. Fortunately, the revolving A-site presents an opportunity to strengthen this interaction by utilizing an external field. Herein, we propose a novel approach to achieving an ordered magnetic dipole moment, which is regulated by a magnetic field via the coupling effect between the chiral passivation molecule and the A-site (formamidine ion) in perovskites. This strategy can increase the molecular interaction energy by approximately four times and ensure a well-ordered molecular arrangement. The quality of the deposited perovskite film is significantly optimized with inhibited nonradiative recombination. It manages to reduce the open-circuit voltage loss of photovoltaic devices to 360 mV and increase the power conversion efficiency to 25.22%. This finding provides a new insight into the exploration of A-sites in perovskites and offers a novel route to improving the device performance of perovskite photovoltaics. [ABSTRACT FROM AUTHOR]

The focus of this study is the structural, electronic, and magnetic characteristics of the ZnSeTe solid solution with chromium impurity. The structure of this solid solution was determined in two steps. At the first stage the internal coordinates of atoms are optimized, and at the second one the lattice parameter relaxation, including re-optimization of internal coordinates, were done. Further, after the introduction of Cr substitution impurity, electronic energy spectra and densities of electronic states were calculated. Significant changes in parameters of the electronic structure and magnetic properties caused by cationic vacancy were revealed. It was found that the doped solid solution of Cr:ZnSeTe is a semiconductor for both electron spin polarizations. The study of the supercell with a cationic vacancy revealed significant differences in the parameters of electronic energy bands as well as magnetic properties, compared with those in crystal with no defects. [ABSTRACT FROM AUTHOR]

The calculation of the magnetic moment of Mn2+ ions in ZnO:Mn (2 at%.) nanocrystals obtained by ultrasonic pyrolysis of aerosol which are responsible for their ferromagnetic properties is given. In order to investigate the influence of structural defects on the value of magnetic moment the samples were heat treated in air. The calculation was performed on the basis of the analysis of magnetization curves and EPR spectra. It was shown that the defective state of ZnO:Mn nanocrystals has a significant effect on the magnetic moment. The values of magnetic moment for the synthesized sample significantly exceed the values of magnetic moment compared to similar nanocrystals obtained by other methods. The assumption is made that this result is due to the presence of an additional component in the magnetization of the defective samples. In addition to the paramagnetism of Mn2+ ions, there may be the paramagnetism of the defective shell of ZnO:Mn nanocrystals. After the elimination of structural defects by heat treatment of samples in air and in a gas mixture with hydrogen, the magnetic moment for Mn2+ ions, which form the ferromagnetic properties of nanocrystals, was determined. The value of this magnetic moment is 0.02µB, where µB is the Bohr mangiton. Such ions, according to the model of bound magnetic polarons, are part of ferromagnetic clusters and take part in the formation of the ferromagnetic properties of the samples. Keywords: magnetic moment, nanocrystals, ultrasonic aerosol pyrolysis, heat treatment, hydrogen.

This study presents an unmanned aerial vehicle (UAV)-borne vector magnetometer (MAG) system and proposes a new data-processing technique for modeling the residual magnetic anomalies of three types of landmines: the metallic antitank M15, the metallic antipersonnel M16, and the minimum-metal antitank M19. The burial depth and magnetic moment of these landmines were estimated using the measured and simulated residual magnetic anomalies based on the proposed UAV-borne vector MAG model. Initial in-flight validation showed a strong correlation between the residual magnetic anomaly maps obtained from measurements and simulations. To verify the detection capability in real-world conditions, the UAV-borne MAG system was tested at the Korean Combat Training Center. Both simulations and experiments demonstrated the effectiveness of the proposed data-processing method and UAV-borne MAG model in accurately modeling the residual magnetic anomalies of landmines with metallic components. This approach will facilitate the automated detection of M15, M16, and M19 landmines with high detection rates and enable accurate classification.

This paper contains data and results from Density Functional Theory (DFT) investigation of 423 distinct X2YZ ternary full Heusler alloys, where X and Y represent elements from the D-block of the periodic table and Z signifies element from main group. The study encompasses both “regular” and “inverse” Heusler phases of these alloys for a total of 846 potential materials. For each specific alloy and each phase, a range of information is provided including total energy, formation energy, lattice constant, total and site-specific magnetic moments, spin polarization as well as total and projected density of electronic states. The aim of creating this dataset is to provide fundamental theoretical insights into ternary X2YZ Heusler alloys for further theoretical and experimental analysis.

Copyright of Journal of Research on Many-Body Systems is the property of Shahid Chamran University of Ahvaz and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Magnetoelectric (ME) composites (x) Ni0.6Mg0.4Fe2O4) + (1-x) (BaZr0.2Ti0.8O3) were synthesized by using solid state reaction technique, followed by uniaxial pressing and sintering process at 1150 °C. Effects of ferrite/ferroelectric composition on structural, electric and magnetic properties were studied. XRD analysis revealed the synthesized composites containing ferrite and ferroelectric phases without any impurity phase. The variation of DC electrical resistivity with respect to temperature revealed the semiconducting behaviour. Dielectric properties were confirmed the conduction mechanism of the composites. By changing ferrite content in composites, the magnetic anisotropy of ferrite phase has been tuned up and studied its role on ME response of the composites. It is observed that the magnetic parameters such as saturation magnetization, magnetic moment and coercivity are found to be decreases with increasing ferrite concentration in composites. Also, it is observed that the sample x = 0.1 has the largest value of saturation magnetization (14.035emu/gm), while sample x = 0.3 shows the lowest value (7.204emu/gm). We interpreted the results in the framework of dynamic piezomagnetic coefficient and also cation distribution in the spinel structure of ferrite phase.

First, this work examines the structural characteristics of the formation of a ZnSeTe solid solution. Further, after the introduction of Fe substitution impurity, electronic energy spectra and densities of electronic states were calculated. Significant changes in parameters of the electronic structure and magnetic properties caused by external hydrostatic pressure were revealed. It was found that the doped solid solution of ZnFeSeTe under normal conditions is a semiconductor for both spin orientations. However, under the action of hydrostatic pressure, this material turns into a metallic state, since the 3d states of iron are now at the Fermi level. Under the influence of pressure, the magnetic moment of the supercell decreases by more than six times, that is, from 4.0 to 0.67 Bohr magnetons. [ABSTRACT FROM AUTHOR]

We are studied the electronic and magnetic properties of the A-site ordered perovskite CaCo3V4O12 within the density-functional theory using the generalized gradient approximation (GGA) with the consideration of strong Coulomb correlations (GGA + U) in the framework of the fully relativistic spinpolarized Dirac linear muffin-tin orbital method of band-structure calculation. The x-ray absorption spectra and x-ray magnetic circular dichroism at the Ca, Co, and V K-edges are investigated theoretically. The effect of the electric quadrupole E2 transitions and magnetic dipole M1 transitions are analysed. The calculated results are in good agreement with experimental data. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin University of Science & Technology is the property of Journal of Harbin University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, we report the induced magnetization in metallic and semiconducting SiCNTs on the adsorption of transition metals. The resultant adsorbed SiCNTs structures showed half-metal-ferromagnetic and ferromagnetic behaviour verifying the induced magnetization. The spin-density of states and bandstructure have also been studied, confirming the induced magnetic behaviour. The strength of the induced ferromagnetic behaviour is varied with the various transition metals and is then related to the calculated magnetic moment in the adsorbed structure. The Cr adsorbed (8,0) SiCNT indicated strong half- metal-ferromagnetic behaviour with a magnetic moment of 5.4 μ B . Only Cu-adsorbed (6,0) metallic SiCNT showed ferromagnetic behaviour among all the simulated structures indicating the impact of transition metal on the SiCNT structures. These promising results will be helpful in designing of devices like spin-valves, MTJs, and MRAMs in the field of spintronics. [ABSTRACT FROM AUTHOR]

Two separate computational algorithms have been used in the current investigation of Full-heusler compounds. One is the pseudo-potential approach used in the Atomistic Tool Kit-Virtual Nanolab, while the other is FP-LAPW method as implemented in WIEN2k. In the computational code, these compounds exhibit mattelic character in both the majority and minority spin channels. According to the WIEN2k and ATK-VNL codes, the computed magnetic moments of these compounds Co2CrZ (Z = As, B, Ga, and Pb) are 4.93 μB and 5.02 μB, 3.00 μB and 3.08 μB, 3.02 μB and 3.16 μB, and 4.07 μB and 4.30 μB, respectively. Between the estimated value and the Slater-Pauling rule, we discovered excellent agreement. These compounds' optical characteristics include reflectivity, refractive index, excitation coefficient, and absorption coefficient, among others. An analysis has been done on the electron energy loss and optical conductivity. Both the electron energy-loss function and the absorption coefficient increase as the energy value increases. As per the results of elastic properties, Co2CrZ compounds with Z = As, Pb are ductile by nature, whereas those with Z = B, Ga are brittle. Co2CrZ (Z = As, B, Ga, and Pb) compounds exhibit metallic behaviour when their Cauchy pressure (CP = C12 - C44) value is positive. [ABSTRACT FROM AUTHOR]

A subclass of ternary intermetallic known as Heusler compounds is being employed in the steel industry to increase material strength. This study examines the structural, electrical, optical, and magnetic properties of Co2VZ (Z=Al, Bi, Ge, Si) compounds using two different methods. First is full potential linearized augmented plane wave (FP-LAPW) method by WIEN2k and second is pseudo potential method by Atomic Tool Kit-Virtual Nano-Lab. The equivalent energy gaps in the minority-spin of Co2VZ (Z= Al, Bi, Ga, Ge) with WIEN2k code, which displays 100% spin polarization, are 0.703, 0.384, 0.186, and 0.67 eV near to the Fermi level. Furthermore, it is discovered that these compounds are absolutely half-metallic ferromagnetic (HMF). With the exception of Co2VBi, which exhibits metallic properties, the aforementioned compounds exhibit 0.525, 0.0, 0.553, and 0.786 eV band gaps in the ATK-VNL code and indicate 100% spin polarization. The magnetic moments of the compounds Co2VZ (Z= Al, Bi, Ga, Ge) are found to be 2.976, 4.003, 1.989, and 3.001 µB, respectively, in the WIEN2k code. The relative magnetic moments of the aforementioned compounds are also 1.991, 3.947, 1.999, and 2.997 µB, according to the ATK-VNL code. [ABSTRACT FROM AUTHOR]

In this work we analyze the statistical thermodynamic functions and magnetic moment of a Dice lattice subject to a normal quantizing magnetic field. Our analysis addresses the Grand Potential and Helmholtz Free Energy, as well as the magnetic moment, entropy and specific heat at constant volume, explicitly determining their magnetic field dependencies in the degenerate statistical regime, replete with de Haas-van Alphen oscillatory phenomenology (and other magnetic field dependence); and also determining their temperature dependencies jointly with magnetic field features in the approach to the zero temperature limit. Furthermore, we evaluate the Grand Potential exactly, for arbitrary temperature and density. Our results are obtained with consideration of the presence of heat and particle baths with fixed chemical potential and they are discussed in relation to other pertinent work on the subject.

Introduction. The article investigated one of the problems of creating exoskeletons — controlling the properties of magnetic rheological fluid in links of variable length with adjustable stiffness. Based on the research of domestic and foreign authors, the development and urgency of the topic was evaluated. The disadvantage of known exoskeleton models has been specified, i.e., the use of absolutely solid links, whose dynamics does not convey the dynamics of the human musculoskeletal system. The scientific research aimed at the formation of a new direction in the development of exoskeletons that accurately simulate the biomechanics of movements. Materials and Methods. Different states of structures of variable-length links with a magnetorheological fluid were studied. It has been noted that the links work on the principle of magnetic shock absorbers and consist of a piston rod, electromagnetic coils, and a housing filled with magnetorheological fluid. The ordering effect of an external magnetic field on the particles of a magnetorheological fluid was visualized and mathematically presented. The significance of such factors as time, charge density, magnetic field strength, as well as vectors of electric and magnetic induction, electric intensity and electric current density for this system was shown. The input parameter affecting the behavior of the magnetorheological fluid was determined. This was the magnetic field intensity. It was shown that the viscosity of the liquid varied depending on the shape of the magnetic particles (oblong or oblate ellipsoid). Results. The dependences that were fundamental for solving the task were investigated and visualized. The magnetic field strength and the angle between the vector directed along a straight line connecting the centers of two micron particles, and the vector of the external magnetic field strength were taken as the basic parameters. It was shown how the magnetic moment, voltage and its antisymmetric part depended on them. It was established that to control the properties of a magnetorheological fluid, it was required to change: – the external magnetic field intensity; – the angle between the external magnetic field intensity and the orientation vector between the dipoles. Two values of force were compared: one – for a given link design, and the other — fixed when walking in the lower leg of a person. The consistency of these indicators was established. Discussion and Conclusion. The scientific research results allowed us to present: – a method for controlling the properties of a magnetorheological fluid by an external magnetic field; – a variable-length link model with adjustable stiffness. The results obtained can be used in modeling multilink structures to create comfortable exoskeletons that interact synchronously with the human musculoskeletal system as a single human-machine system. The development is applicable to solving significant social and economic problems.

This work focuses on study of the structural, electronic, thermodynamic and thermoelectric properties of RbNbCd and RbNbZn Half Heusler (HH), utilizing a full-potential linearized augmented plane wave (FP-LAPW) approach and the Boltzmann transport equation using a constant relaxation time approximation within the context of density functional theory (DFT) as embedded in the WIEN2k code. The structural analysis employed the generalized gradient approximation (GGA) and considered the Birch Murnaghan equation of state (EOS), which results in the stable phase for RbNbCd and RbNbZn. The positive phonon spectra indicate the dynamical stability of the studied RbNbCd and RbNbZn. The compounds under investigation that have no bandgap are metallic, as evidenced by their electronic properties. Their mechanical and thermal stability as well as their anisotropic and ductile character are confirmed by the various elastic and thermodynamic parameters. The lattice thermal conductivity has been calculated. This thorough analysis demonstrates the applicability of the studied RbNbCd and RbNbZn for thermoelectric applications. [ABSTRACT FROM AUTHOR]

The two authors of the study approach the first steps of the impressive scientific career of acad. Ștefan Procopiu (1890-1972), and his fundamental discoveries, namely: determination of the molecular magnetic moment, the Procopiu phenomenon (longitudinal depolarization of colloidal and crystalline solutions), and the Procopiu effect (study of the Barkhausen effect and of magnetic discontinuity).

Triply heavy Occb baryon is considerable theoretical interest in a baryonic analogue of heavy quarkonium because of the color-singlet bound state of three heavy quark (c,b) combination inside. In this paper, we will discuss Occb baryon in the nonrelativistic quark model based on the ansatz approach in hypercentral constituent quark model. The masses of the ground and excited states of the Occb baryon are computed. The hypercentral potential is regarded as a combination of the color Coulomb plus linear confining term and the six-dimensional harmonic oscillator potential in this work. Also, we added the first order correction and the spin-dependent part to the hypercentral potential. The Regge trajectories has been plotted for this baryon and a detailed comparison with previous theoretical calculations is given. Further, using the computed spectroscopic data, the magnetic moments are determined for the ground state based on the nonrelativistic hypercentral constituent quark model. [ABSTRACT FROM AUTHOR]

We have explored the interaction of Ni/Cr with pyridinic N-doped graphene and its influence on the electronic and magnetic characteristics of graphene using a density functional theory (DFT) approach. A 5 × 5 graphene supercell with a single vacancy is modeled. Initially, the concentration of nitrogen atoms is varied in the pyridinic configuration of graphene. The structures, thus obtained, are decorated with Ni/Cr atoms. For configurations without transition metals (TMs), the calculated electronic band structures show a downward shift in Fermi level that decreases as nitrogen concentration increases. Furthermore, it is found that these structures manifest metallic behavior along with some flat bands near the Fermi level. With the addition of Ni/Cr atoms, the movement of the Fermi level toward the conduction band is noticed. The opening of the bandgap at the K-point also varies slightly with the concentration of N atoms and/or the presence of TM atoms. The structures P1N-Ni and P2N-Ni transmute into semiconductors. A significant increase in the magnetic moment is found with the adsorption of the Ni/Cr atom. The analysis of spin-polarized partial density of states proves that higher magnetic moments following TM absorption are mainly on account of the Ni/Cr-3d orbitals and their hybridization with C-2p orbitals. These findings suggest that functionalizing TMs on pyridinic N (Nitrogen)-doped graphene can drastically alter their electronic and magnetic properties. [ABSTRACT FROM AUTHOR]

This paper reports on the synthesis of terbium sesquioxide (Tb2O3) nanoparticles via laser ablation of a solid target in a flowing 95% Ar + 5% H2 binary welding mixture with the use of an ytterbium-doped fiber laser with an average output power of 300 W. We have studied morphological and structural features of the synthesized powder, its thermal behavior, magnetic properties, and densification dynamics during heating to 1450°C in vacuum. The synthesized particles were nearly spherical in shape, with an average size of 13 nm, and had a monoclinic crystal structure, which irreversibly transformed into a cubic structure of symmetry as a result of firing in argon or vacuum at temperatures near 750 and 1050°C, respectively. Using temperature-dependent specific magnetization measurements, we determined their paramagnetic Curie temperature (θp = –11.8 K), Curie constant (C = 11.74 K emu/(mol Oe)), and effective magnetic moment (μeff = 9.69μB/Tb). These data suggest that antiferromagnetic exchange interaction between the terbium ions prevails and that the content of Tb4+ ions in the nanopowder is negligible. We have demonstrated the feasibility of producing transparent Tb2O3 ceramics by consolidating presintered nanoparticles via hot isostatic pressing for 2 h at a temperature of 1450°C and pressure of 200 MPa. [ABSTRACT FROM AUTHOR]

We perform a theoretical analysis of the fate of the local magnetic moment of a quantum dot coupled to a normal metallic lead and a topological superconducting wire hosting Majorana modes at the ends. By means of simple analytical tools and numerical renormalization group calculations, we show that the proximity of the Majorana mode reduces the magnetic moment from 1=4, characteristic of a free spin 1=2, to 1=16. Coupling to the normal lead then causes the Kondo effect, such that the magnetic moment is fully screened below the Kondo temperature. The latter is vastly increased for strong coupling to Majorana mode. [ABSTRACT FROM AUTHOR]

In this work, considering a simplified model we estimate the magnetic moment m associated to two neodymium magnets with different geometries. We investigated how the effect of temperature modifies magnetic properties, such as the intensity of the magnetic field evaluated at the extreme of these magnets, based on these results we present a fictitious anomaly as an didactic purpose inspired by the discussion built throughout the work, which allows illustrating a current problem in the scenario of high energy physics, known as the muon (g-2) anomaly. [ABSTRACT FROM AUTHOR]

In this study, we discuss the magnetic moment of Pcs(4338) and Pcs(4459) hidden-charmed pentaquarks, which are closely related to their substructures. The magnetic moments of these states are calculated with the help of the QCD light-cone sum rules method with quantum numbers I(JP)=0(1/2−) and I(JP)=0(3/2−) for Pcs(4338) and Pcs(4459), respectively. Our predictions for the magnetic moment μPcs=0.34±0.12μN for the Pcs(4338) state, and μPcs=−1.67±0.58μN for the Pcs(4459) state. As a by-product, the magnetic moments of the isospin−1 partners of these states have also been obtained. The magnetic moments are obtained as μPcs=0.63±0.21μN and μPcs=−3.33±1.04μN for the isospin-1 partners of the Pcs(4338) and Pcs(4459) states, respectively. Our results regarding the magnetic moments of these color singlet-singlet type pentaquark states are compared with the results in the literature.

We investigated the magnetic interaction of carbon (C)-transition (Cr/Fe) and rare-earth Gadolinium (Gd) metal co-doped bismuth telluride (BT) systems (CrxCyBi12−xTe18−y, FexCyBi12−xTe18−y and GdxCyBi12−xTe18−y (x = 1, y = 1) supercell structures) by using the density functional theory based on the full-potential linear augmented plane wave method via inclusion of spin polarized calculation. Addition of metal dopant ions in bismuth telluride enhanced the total spin magnetic moment of the entire system (Mtot), which was further increased by the presence of the carbon ion. However, spin magnetic moment of individual dopant ions (MS) was found to be increased or decreased depending upon the position of the metal-carbon dopants relative to each other. This increase in MS is explained by Zener exchange mechanism. C showed a weak MS, in its addition in the BT system. Gd-C co-doping showed highest Mtot and MS compared to Fe-C doped (BT) system. The spin magnetic moment of the system and that of individual dopant ions is influenced by varying the position of C relative to metal dopant ions in BT system. This understanding over the changes in the value of magnetic moment with respect to the position of C ion compared to other dopant ions in the material will lead to the future improvement of magnetic data storage devices. [ABSTRACT FROM AUTHOR]

In this study, nano-sized individual Tb2O3 particles synthesized by the laser ablation method were extensively characterized and assessed as suitable precursors for the fabrication of transparent magneto-optical ceramics without requiring the introduction of grain growth inhibitors and stabilizing additives. The as-produced powder comprised 13 nm particles with a spherical shape and monoclinic crystal structure, whose full transformation into cubic phase was achieved after heating at 950 °C and 700 °C under vacuum and Ar gas, respectively. After subjecting the nanopowder compact to pre-sintering at 1350 °C, the microstructural features were investigated along with their correlation to the optical transmittance of Tb2O3 ceramic hot isostatically pressed (HIPed) for 2 h at 1450 °C under 200 MPa. The as-HIPed sample had a brownish color, with an optical transmittance of 65.3% at a wavelength of 1060 nm and an average grain size of 14 μm. The Verdet constant measured at wavelengths of 633 nm and 1060 nm was 471 rad T−1 m−1 and 142 rad T−1 m−1 to confirm a very high content of magneto-active Tb3+ ions. The obtained results indicate that laser ablation synthesis of nanoparticles followed by pre-sintering and HIP is a promising approach for the manufacture of magneto-optical Tb2O3 ceramics without specific sintering aids. [ABSTRACT FROM AUTHOR]

The parameters of the spin-polarized electronic energy spectrum of ZnSe:T crystals (T = Ti, V, Cr, Mn, Fe, Co, Ni) are studied on the basis of a 2 × 2 × 2 supercell built on the basis of a ZnSe unit cell with a sphalerite structure. The supercell contains 64 atoms, with one Zn atom replaced by one transition 3d element T. The first stage of this study is to calculate in the ideal material ZnTSe parameters of electronic energy bands, dependent on the external hydrostatic pressure. At the second stage, the effect of pressure on the parameters of the electronic energy spectrum in the ZnTSe materials is investigated, taking into account the Zn vacancy. The calculations were performed using the Abinit program. For a better description of strongly correlated 3d electrons of the element T, a hybrid exchange-correlation functional PBE0 with an admixture of the Hartree-Fock exchange potential was used, in which the self-interaction error of these electrons is removed. Based on the obtained spin-polarized electron densities of states, the magnetic moments of the supercells were also determined. A significant effect of pressure on the parameters of electronic energy zones was revealed. So, the ideal ZnTiSe material at zero pressure is a metal for both spin values, but under pressure it becomes a semiconductor. The same material with a point defect, i.e. a vacancy at the site of the Zn atom, exhibits semiconductor properties for both spin orientations at zero pressure. It was found that vacancies radically change the parameters of electronic energy bands. The magnetic moments of the supercell, as integral values of the spin-polarized densities of electronic states, also reflect these changes. Thus, in ZnTiSe material without defects, the magnetic moments of the supercell are 1.92, 2.0 and 2.0, at pressures 0, 21 and 50 GPa, respectively, while in the same material with a vacancy, the corresponding values are 0.39, 0.02 and 0.36. The ideal ZnVSe material at zero pressure is also a metal for both values of the spin moment, but in the presence of a cationic vacancy it is characterized by a pseudogap because the Fermi level is localized in the upper part of the valence band. Ideal ZnFeSe and ZnNiSe crystals are characterized by similar dependences of the electronic energy parameters on the pressure, for both spins. However, the same materials with a cationic vacancy are characterized by the Fermi level immersed in the valence band for a spin up.

Heusler alloys are theoretically predicted to become half-metals at room temperature (RT). The advantages of using these alloys are good lattice matching with major substrates, high Curie temperature above RT and intermetallic controllability for spin density of states at the Fermi energy level. The alloys are categorised into half- and full-Heusler alloys depending upon the crystalline structures, each being discussed both experimentally and theoretically. Fundamental properties of ferromagnetic Heusler alloys are described. Both structural and magnetic characterisations on an atomic scale are typically carried out in order to prove the half-metallicity at RT. Atomic ordering in the films is directly observed by X-ray diffraction and is also indirectly probed via the temperature dependence of electrical resistivity. Element specific magnetic moments and spin polarisation of the Heusler alloy films are directly measured using X-ray magnetic circular dichroism and Andreev reflection, respectively. By employing these ferromagnetic alloy films in a spintronic device, efficient spin injection into a non-magnetic material and large magnetoresistance are also discussed. Fundamental properties of antiferromagnetic Heusler alloys are then described. Both structural and magnetic characterisations on an atomic scale are shown. Atomic ordering in the Heusler alloy films is indirectly measured by the temperature dependence of electrical resistivity. Antiferromagnetic configurations are directly imaged by X-ray magnetic linear dichroism and polarised neutron reflection. The applications of the antiferromagnetic Heusler alloy films are also explained. The other non-magnetic Heusler alloys are listed. A brief summary is provided at the end of this review.

Mixed-ligand complexes of Co(III), Ni(III), Cu(II) and Zn(II) with pyridine and thiocyanate have been synthesized and characterized using elemental analysis, infrared and UV-Vis spectroscopy, thermal analytical techniques, melting point determination, molar conductivity and room temperature magnetic susceptibility measurements. The results suggest that all complexes are stable and molecular with octahedral coordination geometry for the Co(III) and Ni(III) complexes, square planar or tetrahedral geometry for the Cu(II) complex and a tetrahedral geometry for the Zn(II) complex. Evaluation of the antimicrobial activities of the ligands, metals salts and complexes on four bacterial strains (E. Coli, K.Pneumonia, S.typhi and S. flexneri) and four fungal strains (C. Albicans, C., Parapsilopsis, C. tropicalis and C. neoformans) showed higher activity of the complexes compared to the ligands and metals salts. The Co(III) complex showed higher activity than the reference drugs; doxycycline and Penicillin while the Cu(II) complex showed higher activity than the reference antibiotics; doxycycline and nystatin.

Recently, the 'Muon g-2' experiment at Fermilab announced a new measurement of the muon's anomalous magnetic moment with better than one-in-a-million accuracy. While confirming the earlier measurement at the Brookhaven National Lab, it has also strengthened the discrepancy with the theoretical calculations, which have also been performed with the same level of accuracy. We shall discuss the physics behind the anomalous magnetic moment of the muon and some theoretical and experimental aspects of its determination. We shall also touch upon what this discrepancy, if confirmed, would mean for our knowledge of particle physics. [ABSTRACT FROM AUTHOR]

This work details the construction and optimization of a fully automated, custom-built, remote controlled vibrating sample magnetometer for use in spintronics related research and teaching. Following calibration by a standard 6 mm diameter Ni disc sample with known magnetic moment, hysteresis measurements of Nd-Fe-B thin films acquired by this built vibrating sample magnetometer were compared to the data taken using a commercial superconducting quantum interference device and showed very similar results. In plane and out of plane magnetic hysteresis data acquired for 25 nm Fe thin films are also presented. The developed vibrating sample magnetometer is able to achieve a sensitivity approaching 1 × 10−5 emu. Further alterations to the design that may improve beyond this limit are also discussed. [ABSTRACT FROM AUTHOR]

Electronic structure and magnetic properties of Fe 3 Se 4 are calculated using the density functional approach. Due to the metallic properties, magnetic moments of the iron atoms in two nonequivalent positions in the unit cell are different from ionic values for Fe 3 + and Fe 2 + and are equal to M 1 = 2.071 μ B and M 2 = − 2.042 μ B , making the system ferrimagnetic. The total magnetic moment for the unit cell is 2.135 μ B . Under isotropic compression, the total magnetic moment decreases non-monotonically and correlates with the non-monotonic dependence of the density of states at the Fermi level N (E F) . For 7% compression, the magnetic order changes from the ferrimagnetic to the ferromagnetic. At 14% compression, the magnetic order disappears and the total magnetic moment becomes zero, leaving the system in a paramagnetic state. This compression corresponds to the pressure of 114 GPa. The magnetic ordering changes faster upon application of an isotropic external pressure due to the sizeable anisotropy of the chemical bondings in Fe 3 Se 4 . The ferrimagnetic and paramagnetic states occur under pressures of 5.0 and 8.0 GPa, respectively. The system remains in the metallic state for all values of compression. [ABSTRACT FROM AUTHOR]

A typically new semi-analytical finite element approach has been used to calculate the force and moment of permanent magnet bearing (PMB) in this article. PMB stator and rotor consist of ring-type cylindrical magnets having an axial magnetization. This article focuses on the characterization of magnetic moment, stiffness matrix, model validation, and comparisons of the moment with other simulating software. This article also explains how angular stiffness or resisting magnetic moment of PMB improves with the change of rotor magnet length and positional shift of the rotor. [ABSTRACT FROM AUTHOR]

The pressure dependence of magnetic moment in CeMg 3 and PrMg 3 has been studied through ab initio electronic structure calculations based on density functional theory (DFT). Positive as well as negative pressure conditions were simulated by different degrees of unit cell compression or expansion and a fit of the total energy to the Birch–Murnaghan equation of state. At ambient and negative pressures, the calculated magnetic moments for both the compounds reveal localized behaviour of 4 f electrons. For increasing positive pressures, the magnetic moment of Ce in CeMg 3 has been observed to diminish smoothly, becoming zero at a critical pressure of P C ∼ 18 GPa indicative of pressure induced moment instability caused by an increase of f -conduction electron hybridization leading to delocalization of the 4 f electrons. In contrast, the magnetic moment of Pr in PrMg 3 does not show appreciable change with pressure, indicating strongly localized nature of the 4 f electrons. [Display omitted] • Strong delocalization behaviour of 4f electrons of Ce with respect to pressure. • 4f electrons of Pr shows localized behaviour and weak pressure dependence. • CeMg 3 shows a critical pressure of 18 GPa, where both spin and orbital moment vanishes. • Strongly correlated behaviour at low temperature and above 18 GPa pressure is expected. • Ce in CeMg 3 shows 4f1 configuration and Pr in PrMg 3 shows 4f2 configuration. [ABSTRACT FROM AUTHOR]

This study employs density functional theory (DFT) using Wien2k to comprehensively analyze the essential properties of two half-Heusler alloys, KCrSi and KCrGe. Our findings demonstrate that the ferromagnetic Type 2 configuration exhibits superior stability over non-magnetic and antiferromagnetic states for all KCrZ (Z = Si, Ge) alloys. These alloys exhibit complete spin polarization and half-metallic character, with calculated magnetic moments of 3 μB for both KCrSi and KCrGe. The Curie temperature (T C) is determined using the mean field approximation. Mechanical stability is assessed through second-order elastic constants (SOECs), and electronic properties are analyzed using local spin density approximation (LSDA), Perdew-Burke Generalized Gradient Approximation (PBE-GGA), and Tran-Blaha modified Becke-Johnson (TB-mBJ) schemes, confirming the retention of the half-metallic nature. The negative enthalpy of formation (ΔH) suggests material stability. The use of semi-classical Boltzmann theory, incorporated through the sophisticated scheme of BoltzTraP, explores transport coefficients. High pressures and temperature discrepancies in thermodynamics are considered by implementing the quasi-harmonic Debye approximation to illustrate stability. Finally, optical properties are summarized to assess the applicability of this alloy for optoelectronic applications. The overall characteristics of these particular alloys suggest potential applications in sustainable thermoelectric and optoelectronic features. • The stability in cubic structure is established with the help of structural optimization, and mechanical stability criteria. • The high Seeback coefficient and low thermal conductivity yield a high figure of merit ZT at 900 K. • The alloy has potential applications in thermoelectric technology and optoelectronic devices. [ABSTRACT FROM AUTHOR]