Magnetic Properties Of Transition Metals Research Articles

Quantum mechanical effects controlling the magnetic properties of transition metal based nanoglass

In previous investigations, it was reported that transition metal-rich amorphous alloys consist of distorted bcc nano-clusters. Two types of amorphous metals are of interest due to their physical properties: (1) metallic glasses and (2) nanoglasses. Using the example of Fe90Sc10 alloys, this paper discusses quantum mechanical effects leading to new features and properties of these materials. The metallic glass Fe90Sc10 can be prepared by rapidly quenching the melt. In these materials, the atoms are structurally located next to each other without forming grain boundaries. Due to the variation of atomic distances, these metallic glasses are divided magnetically into nano-clusters. The second group of amorphous materials, called metallic nanoglasses, consists of amorphous nanometer-sized clusters (frequently called nanograins) with sizes of about 10 nm or less. These nanograins are interconnected by interfaces. One of the features of nanoglasses is the properties of their interfaces. The properties of interfaces seem to be controlled by quantum mechanical effects. In this paper, some of these quantum mechanical effects will be discussed based on the experimentally observed properties of Fe90Sc10 nanoglasses.

Structural, dielectric, and magnetic properties of transition metals substituted strontium aluminates for energy storage applications

Structural, dielectric, and magnetic properties of transition metals substituted strontium aluminates for energy storage applications

Structure, electronic, and magnetic properties of 3d transition metal intercalated borophene/BP heterostructures

AbstractThe intercalation of various atoms or molecules has become one promising way to manipulate the electronic and magnetic properties of layered materials. Using density functional calculations, we explored the 3d transition metal (TM) intercalated α‐borophene/black phosphorus (α‐B/BP) heterostructure, TM@(α‐B/BP) (TM = Sc‐Ni), on their structure, electronic and magnetic properties. Our results demonstrate that TM@(α‐B/BP)s can be ferromagnetic (FM), antiferromagnetic (AFM) and nonmagnetic depending on the choice of TM atoms, and most systems have large magnetic anisotropic energy. Particularly, Ti@(α‐B/BP) is AFM semiconductor with Néel temperature of 470 K, which is much higher than room temperature. Moreover, the electronic and magnetic properties of TM@(α‐B/BP)s can be further altered by the TM intercalation concentration. Our results provide a feasible way to design promising candidates for applications in electronic and information storage devices.

First-principles investigates on the electronic structure and magnetic properties of V-, Cr-, Mn-doped two-dimensional Ga2O3

In this paper, the electronic and magnetic properties of transition metals (TM) doped two-dimensional (2D) Ga2O3 are investigated based on first-principles calculations. The formation energies under O-rich conditions are significantly lower than those under O-poor conditions, making it easier to synthesize the TM-doped 2D Ga2O3 systems under O-rich conditions. The introduction of V, Cr, and Mn has successfully introduced magnetism into 2D Ga2O3. The V3+, Cr3+, and Mn3+ ions are left with 2, 3, and 4 unpaired electrons occupying different d orbitals, further leading to magnetic moments of 2, 3, and 4 μB in the three doped systems, respectively. Biaxial strain can effectively manage the bandgap of the TM-doped Ga2O3 systems. This work proves that doping V, Cr, and Mn into 2D Ga2O3 is an effective way to broaden the application of 2D Ga2O3 in dilute magnetic semiconductor (DMS)-based devices.

Tunable electronic and magnetic properties of 3d transition metal ion-doped monolayer graphitic-ZnO: An ab-initio calculation

Electronic and magnetic properties of transition metal (TM) ion-doped monolayer zinc oxide (ML-ZnO) have been analyzed using ab-initio calculations in the frame work of density functional theory. Spin–spin interaction study reveals that Cr, Mn, Fe and Cu doped at Zn site of ML-ZnO show stable ferromagnetic ordering along with the half-metallic behavior for most of the cases. The electronic and magnetic properties of the pristine system can also be modified by using co-doping. 3d orbital electrons of the dopants are primarily responsible for the origin of magnetic moment and the remaining part comes from the 3d and 2p orbital electrons of Zn and O atoms, respectively. Moreover, the magnetic ordering in Fe-doped ML-ZnO can change with the doping distance between the dopants.

Interdependence between structural and magnetic properties of transition metal doped multiferroic perovskite ferroelectric ceramics and its sustainable applications: Review

Multiferroic perovskite materials are considered brilliant & suitable materials for power storage and electrical energy conversion because of their excessive power efficiency, temperature stability, and occasional dielectric loss. The electric houses of such multiferroic substances are modify-made through ferroelectric and ferromagnetic parts and feature unfolded first-rate avenues in an electrochemical supercapacitor, photovoltaic, and optical tool applications. Dopants significantly optimize such materials' magnetic and structural properties owing to suitable applications like capacitors, multi-aspect capacitors (MLCs), and strength capability gadgets. This survey features the logical progressions announced in transition metal doped barium titanate multiferroic ferroelectric ceramics for energy applications by optimizing their magnetic properties. This paper begins off evolved with a quick advent of Barium titanate and a dialogue at the outcomes of diverse dopants with the aid of using extraordinary synthesis techniques, and their outcomes on structural and magnetic homes also are depicted. Ultimately, this assessment summarizes the diverse doping outcomes, which paves the manner for destiny studies in this multiferroic substantial for sustainable tool applications.

Transition in electronic and magnetic properties of transition metal embedded semimetallic B-graphyne.

Spintronics is extremely important in the future development of information technology. Notably, two-dimensional carbon materials with atomically thick and p-electron systems have great potential for application in ultrathin spintronic devices. B-graphyne (B-GY) is a recently proposed two-dimensional carbon allotrope with double Dirac cones. It is a promising nanomaterial for high-speed spintronic devices due to its ultra-high Fermi velocity and thermodynamic stability. We tune the electronic and magnetic properties of B-GY by doping 3d transition metals (TM) (Cr, Mn, Fe, Co, Ni) based on first-principles calculations. After doping, TM forms strong covalent bonds (Fe, Co, Ni) and ionic bonds (Cr, Mn) with adjacent C atoms. The system of TM-doped B-GY (TM@B-GY) is transformed from a semimetal for B-GY to a metal (Cr, Mn, Fe, Co), but Ni@B-GY is still semimetal. Among them, Co@B-GY is approximately a half-metal. Moreover, TM (except Ni) can induce the magnetism of B-GY to undergo spin splitting. The TM d-orbitals are strongly coupled to the C p-orbitals, which play an important role in inducing magnetism. The results show that the tunable electronic and magnetic properties of TM@B-GY are promising as a high-speed spintronic device. Our research helps advance the study of semimetallic carbon allotropes in the field of spintronics.

Structures, electronic and magnetic properties of transition metal inserted W6O18 clusters

Structures, electronic, and magnetic properties of transition metal (TM) inserted W6O18 clusters have been investigated by using density functional theory. The Ti@W6O18, Ni@W6O18, Zr@W6O18, Rh@W6O18, W@W6O18, and Ir@W6O18 clusters are more structurally stable while the V@W6O18, Fe@W6O18, Zn@W6O18, Y@W6O18, Nb@W6O18, Pd@W6O18, La@W6O18, Re@W6O18, Hg@W6O18 clusters are more chemically stable. The amount of charge transfer between the TM atoms and W6O18 clusters decreases with the increase of the subgroup number except for subgroup number is equal to 11 and 12. The d orbital of the 3d TM@W6O18 clusters start to make the main contributions to Fermi level except for the Cu@W6O18 and Zn@W6O18 clusters.

A comparative DFT study of structural, electronic, thermodynamic, optical, and magnetic properties of TM (Ir, Pt, and Au) doped in small Tin (Sn5 & Sn6) clusters

ABSTRACT The geometric, electronic, thermodynamic, optical, and magnetic properties of Sn5 and Sn6 clusters after doping with transition metals (TM) – Gold, Platinum, and Iridium have been investigated. This investigation has been performed by employing density functional theory with B3LYP hybrid functional using LanL2DZ and SDD basis sets. It was observed that Pristine Sn5 / Sn6 clusters gain more stability and effectiveness after doping transition metals in middle and side positions. The TM doped Sn5 clusters are more stable chemically and energetically than TM doped Sn6 clusters whereas Sn4-Au-M cluster is more stable than other clusters. Imaginary frequency was not found for Sn4-Au-M cluster according to IR spectroscopy study. So, this cluster can be found naturally and possesses magnetic susceptibility. Also, Au-M doped Sn5 cluster is spontaneous and more stable thermodynamically. Due to preferable structural, electronic, thermodynamic, and magnetic properties, the optically active Sn4-Au-M cluster could be suitable for technological applications.

Optoelectronic and magnetic properties of transition metals adsorbed Pd2Se3 monolayer

In this article, the optical, magnetic, and electronic of pristine and transition metals (TM) adsorbed Pd2Se3 were systematically researched by density functional theory. The results reveal that the most stable position of Pd2Se3 monolayer adsorbed by various TM is different. The band structures of Au-, Cu- and Sc–Pd2Se3 structures demonstrate nonmagnetic metal behaviour, while the Co- and Cr–Pd2Se3 structures display magnetic metal properties. Meanwhile, the Ni- and Pt–Pd2Se3 systems show nonmagnetic semiconductor character, and Fe- and Mn–Pd2Se3 systems exhibit magnetic semiconductor features. Moreover, the work function of Au-, Cu-, Co-, Mn- and Fe–Pd2Se3 structures is lower than Pd2Se3 monolayer, which demonstrates that these structures have good electron emission characteristics. Interestingly, after the adsorption of TM atom, the light absorption of Pd2Se3 system in various regions is boosted to varying degrees, indicating that the introduction of TM atom can improve the light absorption of Pd2Se3 system in ultraviolet, visible and infrared regions. Therefore, it demonstrates that TM-Pd2Se3 systems can be used to fabricate spintronic, photocatalysts and optoelectronic devices.

First-principles study of structural, electronic and magnetic properties of transition metal doped Sc2CF2 MXene

The electronic and magnetic properties are investigated for pristine Sc2CF2, Sc2CF2-VSc (Sc2CF2 with single Sc vacancy), and Sc2CF2-dTM (Sc2CF2 doped with transitional metals TM, TM = Cr, Fe, Hf, Mn, Mo, Nb, Re, Ta, Ti, V, W, Y, or Zr) by first-principles calculation. The result indicates that Sc2CF2-dTM (TM = Ti, Zr, Nb, Hf, Ta, or W) monolayers are more stable than the other systems through the analysis of binding energies. The introduction of the Sc-vacancy and substitution doping of Hf, Mo, Nb, Re, Ta, Ti, W, or Zr atoms result in the semiconductor–metal transition for the Sc2CF2 monolayer, while the introduction of doped Cr, Fe or Y atoms doesn’t change the semiconductor character of Sc2CF2 monolayer and the introduction of doped V or Mn atoms results in the semimetal character. The substitution doping of V, Cr, Fe, or Mn atoms leads to significant magnetism. Charge transfer is further explored by the analysis of the charge density difference, the planar averaged charge density, and Bader charge. The effective mass and electron localization function are also analyzed.

Silicene Nanoribbon Based Spin-Field Effect Transistor With Spin Filtering and Spin Seebeck Effects

The present work reports the application of density functional theory (DFT) and non-equilibrium Green's function (NEGF) formalism based framework to investigate the voltage-dependent spin transport properties for a Z-shaped silicene nanoribbon (SiNR) based spin-field effect transistor (spin-FET). The structural and magnetic properties of transition metal passivated zigzag-SiNR with symmetric and asymmetric hydrogenation at other ends have been analyzed to identify the suitability of these materials as a potential source and drain electrodes for the proposed spin-FET model. The analysis reveals that the device displays an excellent spin filtering effect and oscillatory transfer characteristics in the parallel configuration (PC) mode. Also, a high drive current and I <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$ _{ON}$</tex-math></inline-formula> /I <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$ _{OFF}$</tex-math></inline-formula> ratio and both positive and negative transconductance are achieved. Additionally, the device generates a highly spin-polarized thermal current with the spin Seebeck effect and high spin filtration efficiency under the influence of temperature gradient. These findings defend that the proposed device model can be treated as multifunctional spintronic and spin caloritronic devices.

Induced ferromagnetism on late transition metals adsorbed on Antimony Arsenide monolayer from First-Principles

We investigate the structural, electronic and magnetic properties of transition metal (including Mn, Fe, Co, Ni, Cu, Rh and Pd) adsorbed on SbAs monolayer by using density functional theory. We found that an induced magnetic moment is observed for Mn, Fe, Co and Rh transition metal atoms, while in the case of Cu and Ni it is suppressed by local distortions. Our calculations show that Mn, Fe, Co and Rh can induce total spin magnetic moment of 4.86μB, 3.51μB, 1.99μB and 0.90μB, respectively. The origin of magnetism lays is their d orbital and depends on its filling level. In particular, the total magnetic moment decreases with increasing the number of d electrons. Among the studied transition metals, Mn seems to be the most promising candidate for the introduction of ferromagnetic ordering into SbAs, as it showed a high magnetic moment close to 5μB. Overall, the analysis of the electronic and magnetic properties indicates that transition metal doped SbAs are promising two-dimensional magnetic systems.

Tunable Electric and Magnetic Properties of Transition Metal@Nx Cy -Graphene Materials by Different Metal and Defect Types.

Transition metal@Nx Cy -graphene (TM@Nx Cy -GR) materials have been widely used as redox reaction catalysts in the field of fuel cells due to their low cost and high performance. In the present work, we systematically investigate the effect of different metal and defect types on the electro-magnetic properties of TM@Nx Cy -GR materials using first principles calculations. Our simulations show that TM@N3 -GR (the minimum defect size) and TM@N7 -GR (the maximum defect size) materials always possess metallic property regardless the metal type. However, doping different TM can regulate the medium defects (TM@N2 C2 -GR-I and TM@N2 C2 -GR-II) among metallicity, half-metallicity and semi-conductivity. In addition, we found that different TM and defect type largely affects the magnetic moment. The spin density and projected density of state calculations show that the net charges of the defect structure are mainly located near the hole, and the magnetic regulation comes from the coupling of TM-d orbital with carbon (nitrogen)-s(p) orbitals. The present study provides abundant valuable information for the TM@Nx Cy -GR materials designs and applicants in the future.

Magnetic and electronic properties of transition metal doped aluminium nitride: Haldane’s approach combined with ab initio results

The electronic and magnetic properties of transition metal (Mn and Cr) doped Aluminium Nitride (AlN) in the wurtzite structure is studied using the single impurity Anderson model (SIAM) extended to semiconductors by Haldane. An equation of motion method based on Green’s function was used to obtain the effective spin decomposed impurity levels. The calculated electronic density of states of Mn and Cr valence orbitals exhibit half metallic properties when the impurity is strongly coupled to the host. The effect of the Coulomb correlation and orbital hybridization on the formation of a localized moment in such systems is investigated. Magnetic impurities are often responsible for the inelastic scattering of conduction electrons. For a configuration averaged random ensemble of impurities, initially non-polarized host band develops a small moment presumably due to the potential scattering.

Exploration of structural, morphological and magnetic properties of transition metal doped SnO2 films grown using pulsed laser deposition

In this paper, structural, surface morphology, and magnetic properties of transition metal (TM = Ni) doped SnO2 thin films (TFs) have been reported. Thin films of Ni doped SnO2 were deposited on LaAlO3 (100) substrate using pulsed laser deposition method. The X-ray diffraction (XRD) confirmed that all the films have a single phase with the tetragonal rutile structure. The multiple peaks observed in the XRD pattern clearly show the polycrystalline nature of the films and textured along (101) orientation. The average surface roughness (Ra) and root mean square roughness (Rq) measured using AFM micrographs was found to increase initially from 4.96 nm to 11.2 nm and 6.14 nm–14.0 nm until 5% Ni doping and then finally Ra and Rq decreases to 2.87 nm 3.69 nm respectively for 20% Ni-doped SnO2 films, respectively. The dc magnetization measurements indicate that all films display room temperature ferromagnetism (RTFM). The saturation magnetization calculated using M − H loops was found to increase from 1.4 emu/cm3 to 7 emu/cm3 for 20% Ni doped SnO2. The RTFM observed in Ni-doped SnO2 films has been explained based on the bound magnetic polaron model.

First principles study of structural, electronic and magnetic properties of transition metals doped SiC monolayers for applications in spintronics

First principles investigations were carried out to explore the prospects of using silicon carbide (SiC) monolayers in spintronics. The structural, electronic and magnetic properties of Ti, V, Cr, Mn and Fe doped SiC monolayers were studied in detail in framework of density functional theory (DFT). These dopants changed the band structure of SiC by introducing gap states and thus altered the electronic and magnetic character of the host. The results indicated that Ti did not produce any magnetic state whereas Mn and Cr exhibited ferromagnetism (FM), and V as well as Fe displayed anti-ferromagnetism (AFM) as stable configurations in the matrix. The calculated values of magnetic moments are 0 μB, 1.24 μB, 2.37 μB, 3.01 μB, and 2.21 μB for dopants Ti, V, Cr, Mn and Fe respectively in the host. The dopants reveal 3d-2p hybridization with exchange interactions taking place through charge hopping. The analysis indicated that magnetic exchange takes place in Mn:SiC and Fe:SiC via super-exchange whereas in Cr:SiC via double exchange interactions. The Mn doped SiC monolayer appeared to offer highest Curie temperatures with half metallic nature and highest magnetic moment which points to its suitability as potential diluted magnetic semiconductor for different spintronic applications.

Magnetic modification of transition-metal-atom–adsorbed blue phosphorus monolayer: A first-principles study

Based on density functional theory, we systematically studied the electronic and magnetic properties of transition metal (TM) atoms (Sc, Ti, V, Cr, Mn, Fe, Co, Ni and Cu atoms) adsorbed on blue phosphorus monolayer by using first-principles calculations. In addition to Ni atoms, the adsorption of Sc, Ti, V, Cr, Mn, Fe, Co and Cu atoms can produce magnetic moments on the blue phosphorus monolayer. The source of the magnetic moment is determined by the hybridization mechanism between the TM atoms and the blue phosphorus monolayer. We also studied the effect of biaxial strain on the magnetism of the blue phosphorus adsorption system. The results show that the magnetic moments of the Ti, V and Cu atoms adsorbed blue phosphorus monolayers are rather sensitive to the strain, and other TM atoms adsorbed blue phosphorus systems will not be affected by the strain. Therefore, blue phosphorus has broad application prospects in nanoelectronics and spintronic devices.

Transition metal doped arsenene: Promising materials for gas sensing, catalysis and spintronics

Based on first-principles calculations, we systematically investigated the stability, electronic and magnetic properties of transition metal (TM)-doped arsenene (TM = Cr, Mn, Fe, Co, Ni, and Cu) with O2 adsorbed, and further explored the catalytic performance of TM-doped arsenene for CO oxidation. The substitutions of TM atoms induce the magnetic ground states of arsenene exception for Cu, which arises from the strong hybridizations of 3d orbitals of TM atoms and 4p orbitals of surrounding As atoms. Mn-, Co- and Ni-doped arsenenes are half metals showing potential applications in spintronics. O2 molecule prefers to chemisorb at the TM-doped arsenene systems with larger adsorption energies than those for perfect arsenene, indicating TM-doped arsenene can be used as O2 sensor with promoted sensitivity. It is worthy to notice that Cr-doped arsenene transforms from a diluted magnetic semiconductor to a magnetic metal owing to the adsorption of O2. The partially occupied O 2p and Cr 3d orbitals suggest that O2 molecule is highly activated, which is consistent with the largest elongation of OO bond length. The barrier of CO oxidation on Cr-doped arsenene through Langmuir-Hinshelwood (LH) mechanism is 0.72 eV, which implies that TM-doped arsenene may be promising single atom catalysts for the oxidation of CO.

Magnetic and optical properties in degenerated transition metal and Ga co-substituted ZnO nanocrystals

In order to study the influence of itinerant electrons on magnetic properties of transition metal substituted ZnO nanocrystals, nanopowders containing different amounts of Ga and fixed amounts of Fe, Ni and Mn ions were synthesized. The ions of different transition metals and Ga were successfully introduced into the ZnO structure using solvothermal synthesis method. X-ray diffraction, scanning electron microscopy, hard X-ray photoelectron spectroscopy and Rietveld refinement were used to characterize the synthesized nanocrystals. Optical measurements revealed that Ga substitution can change the light transmittance/absorption in the infrared part of the electromagnetic light spectrum due to itinerant electrons in the nanocrystals, as well as influence the magnetic properties of the obtained nanocrystals.