Fe Monolayer Research Articles

Controllable magnetic ground states in metal diiodide MI2 (M: Fe, Co, and Ni) monolayers by electric field

We investigated the controllable magnetic ground states of 1T metal diiodide MI2 (M: Fe, Co, and Ni) monolayers by applying the electric field. To do so, we utilized the generalized Bloch theorem within the density functional theory on the primitive unit cell to examine the appearance of three possible magnetic ground states, namely, ferromagnetic, spiral, and antiferromagnetic states from the specified spiral vector. We found that the ground state can be changed as the electric field increases but depends on the lattice parameter. In general, the spiral ground state exists as the electric field is taken into account, thus all these materials are prominent as multiferroics. Also, based on the competition between ferromagnetic and antiferromagnetic exchange interactions, we observed that for FeI2, the transition from the ferromagnetic exchange to the antiferromagnetic exchange happens as the electric field increases, while CoI2 and NiI2 tend to preserve their original exchange interaction. This implies that only the magnetic state in FeI2 sensitively depends on the electric field.

Identification of the optimal site for oxygen adsorption in chemisorbed and oxidized states on pseudomorphic Fe/Ru(0001) surface: A density functional theory computational investigation

The oxidation state and charge distribution of FexOy binaries, including strained monolayers on transition metal surfaces, is a topic of significant interest. The p(2 × 2) and c(4 × 2) superstructures are two stable surface structures of chemisorbed oxygen on the pseudomorphic Fe/Ru(0001) surface that may coexist at 0.25 ML oxygen coverage. Density functional theory calculations were used to investigate the possibility of these two structures occurring on the surface. The calculations considered the effect of magnetic ordering on the choice of adsorption site for oxygen. Paramagnetic ordering of the Fe monolayer favors oxygen adsorption at the hcp site, while antiferromagnetic ordering favors oxygen adsorption at the fcc site at 0.25 ML oxygen coverage. Interestingly, in the case of antiferromagnetic ordering, although the adsorption of 1 ML coverage of oxygen for the oxidation reaction energetically prefers the hcp site, the chemisorbed structures at 0.25 ML coverage are found to prefer the fcc site on the pseudomorphic Fe/Ru(0001) surface. The DFT calculations suggest that both the p(2 × 2) and c(4 × 2) structures of oxygen are exothermic, indicating the possibility of coexistence on the pseudomorphic Fe/Ru(0001) surface and occurrence at room temperature. However, the use of the Hubbard potential parameter, which is used to correctly describe the electronic band structure of FeO and other Mott insulators, also revealed that the oxidation reaction of the pseudomorphic Fe monolayer is endothermic on the Ru(0001) surface.

Significant enhancement of perpendicular magnetic anisotropy in Fe/MoSi2N4 by hole doping

This study proposes a novel approach to enhanced the perpendicular magnetic anisotropy (PMA) of Fe adsorbed on a MoSi2N4 substrate through hole doping. First principles calculations are employed to investigate the PMA of freestanding Fe and Fe/MoSi2N4 complex system. It is found that the PMA of Fe atom slightly increases from freestanding Fe monolayer to the Fe/MoSi2N4 system, which is attributed to the overlap between Fe-3d and N-2p orbitals. More interestingly, it is found that the PMA of Fe atoms in Fe/MoSi2N4 can be further enhanced by hole doping, which enables the PMA to increase significantly, up to four times the original value. This finding provides a promising way to enhance the PMA in two-dimensional (2D) spintronic devices. These results offering potential applications in developing advanced 2D spintronic devices.

Carrier doping modulates the magnetoelectronic and magnetic anisotropic properties of two-dimensional MSi2N4 (M = Cr, Mn, Fe, and Co) monolayers.

Through extensive density functional theory (DFT) calculations, our investigation delves into the stability, electrical characteristics, and magnetic behavior of monolayers (MLs) of MSi2N4. Computational analyses indicate intrinsic antiferromagnetic (AFM) orders within the MSi2N4 MLs, as a result of direct exchange interactions among transition metal (M) atoms. We further find that CrSi2N4 and CoSi2N4 MLs with primitive cells (pcells) exhibit half-metallic properties, with respective spin-β electron gaps of 3.661 and 2.021 eV. In contrast, MnSi2N4 and FeSi2N4 MLs with pcells act as semiconductors, having energy gaps of 0.427 and 0.282 eV, respectively. When the SOC is considered, the CrSi2N4, MnSi2N4 and FeSi2N4 MLs are metals, while the CoSi2N4 ML is a semiconductor. Our findings imply the dynamics and thermodynamic stability of MSi2N4 MLs. We have also explored the influence of carrier doping on the electromagnetic attributes of MSi2N4 MLs. Interestingly, charge doping could transform CrSi2N4, MnSi2N4, and CoSi2N4 MLs from their original AFM state into a ferromagnetic (FM) order. Moreover, carrier doping transformed CrSi2N4 and CoSi2N4 MLs from spin-polarized metals to half-metals (HMs). It is of particular note that doping of CrSi2N4 MLs with +0.9 e per pcell or more holes caused a switch in the easy axis (EA) to the [001] axis. The demonstrated intrinsic AFM order, excellent thermodynamic and kinetic stability, adjustable magnetism, and half-metallicity of the MSi2N4 family suggest its promising potential for applications in the realm of spintronics.

Magnetism and magnetic properties of 3d transition metal monolayer on Pd(1 0 0)

First-principles calculations based on density functional theory (DFT) are utilized to examine the effect of 3d transition metal (TM) monolayer on the Pd (001) substrate. Four transition metal (Cr, Mn, Fe, and Co) monolayers are investigated in the middle of a 1 × 1 × 7face-centered cubic supercell. Two different structures are considered, one with the TM monolayer sandwiched between the Pd atoms in the supercell creating a substrate-cap structure (Pd/TM/Pd), while the other structure is left uncapped (Pd/TM). We found that the magnetocrystalline anisotropy energy of the (Pd/TM/Pd) structure is more significant than the uncapped structure (Pd/TM). Furthermore, the ground state of the Cr and Mn monolayers is antiferromagnetic, while the ferromagnetic ordering is the ground state for the Fe and Co monolayers. In addition, magnetic moments, anisotropy field, and maximum energy products are studied.

Chitosan-g-polyacrylonitrile ZnO nano-composite, synthesis and characterization as new and good adsorbent for Iron from groundwater

The highly poisonous, non-biodegradable heavy metals present serious concern in wastewater environmental sustainability and human health. Using adsorption is an effective technology for the treatment of this kind of water. Therefore, developing efficient and cost-effective adsorbents considers a significant and an emerging topic in the field the water purification. Chitosan grafted polyacrylonitrile (Cs-g-PAN) was facially fabricated via graft polymerization using ammonium persulfate (APS) as the initiator. The simple ultrasonic technique was used for doping ZnO nanoparticles into the Cs-g-PAN matrix to prepare chitosan-grafted polyacrylonitrile/ZnO (Cs-g-PAN/ZnO). For comparative study, pure ZnO and nanocomposite of PAN doped with ZnO (PAN/ZnO) were also prepared. XRD, FTIR, SEM, TEM, BET, EDS, and TGA measurements were conducted to confirm the morphological and structural properties of the prepared materials. Cs-g-PAN/ZnO possesses a specific surface area of 20.23 m2/g with a pore size of 31.58 nm and pore volume of 0.16 cm3 g−1. The adsorption behavior toward Fe(II) as a pollutant for groundwater was studied for the synthesized materials.The effect of pH (4–8), contact time (5–60 min), adsorbent dose (0.01–0.3 g), and different temperature degrees (278, 288, 298, 308, and 318 K) on the removal of iron (II) has been conducted. The removal efficiency was achieved 100 % under the optimum condition, at pH = 7, contact time 30 min, adsorbate concentration 0.93 mg/L, and adsorbent dosage 0.05 g/L at room temperature. Langmuir and Freundlich's isothermal and kinetic studies have been analyzed to determine the adsorption mechanism of Fe(II) ions on the synthesized nanomaterials. The adsorption process of Fe(II) over the surface of prepared catalysts proceeded via the Langmuir model and pseudo-second-order reaction kinetics with R2 > 0.99. Suggesting the formation of Fe(II) monolayer over the adsorbent surface and the rate-limiting step is probably controlled by chemisorption through sharing the electrons between Fe+2 and the prepared catalyst.

Computational Screening of Two-Dimensional Metal-Organic Frameworks as Efficient Single-Atom Catalysts for Oxygen Reduction Reaction.

The development of efficient and inexpensive oxygen reduction reaction (ORR) catalysts is crucial for renewable energy technologies. Herein, using density functional theory (DFT) methods and microkinetic simulations, we systematically investigated the ORR catalytic performance of a series of 2D metal-organic frameworks M3 (HADQ)2 (HADQ=2,3,6,7,10,11-hexaamine dipyrazino quinoxaline). It shows that all 2D M3 (HADQ)2 (M=Cr, Mn, Fe, Co, Ni, Cu, Ru, Rh and Pd) monolayers are metallic, due to π-conjugated crystal orbitals centered on the central metals and ligand N atoms. The catalytic activity of M3 (HADQ)2 depends on the binding strength between ORR intermediates and metal species, and can be tuned via changing the central metals. Among these candidates, Rh3 (HADQ)2 and Co3 (HADQ)2 show superior ORR performance to Pt (111) with high half-wave potentials of 0.99 and 0.93 V, respectively. Moreover, the screened two catalysts have excellent intermediate-tolerance ability for dynamic coverage of oxygenated species on the active sites. Our work provides a new path towards developing efficient ORR electrocatalysts.

The influence of adatom diffusion on the formation of skyrmion lattice in sub-monolayer Fe on Ir(111)

Room temperature grown Fe monolayer (ML) on the Ir(111) single crystal substrate has attracted great research interests as nano-skyrmion lattice can form under proper growth conditions. The formation of the nanoscale skyrmion, however, appears to be greatly affected by the diffusion length of the Fe adatoms on the Ir(111) surface. We made this observation by employing spin-polarized scanning tunneling microscopy to study skyrmion formation upon systematically changing the impurity density on the substrate surface prior to Fe deposition. Since the substrate surface impurities serve as pinning centers for Fe adatoms, the eventual size and shape of the Fe islands exhibit a direct correlation with the impurity density, which in turn determines whether skyrmion can be formed. Our observation indicates that skyrmion only forms when the impurity density is below 0.006/nm2, i.e., 12 nm averaged spacing between the neighboring defects. We verify the significance of Fe diffusion length by growing Fe on clean Ir(111) substrate at low temperature of 30 K, where no skyrmion was observed to form. Our findings signify the importance of diffusion of Fe atoms on the Ir(111) substrate, which affects the size, shape and lattice perfection of the Fe islands and thus the formation of skyrmion lattice.

Evolution of the Fe-Co magnetism and magnetic proximity effects in alternate Fe/Co monolayers on nonmagnetic Cu3Au(001)

Magnetic heterostructures with ferromagnetic/nonmagmetic interfaces are very interesting materials due to the possibility to switch the magnetization, to control the induced magnetic moment, and also due to interfacial effects. The tuning of the spin-orbit coupling in magnetic materials allows engineering new spintronic devices. Using density functional theory, the induced local magnetic moments in copper and gold surface atoms of ${\mathrm{Cu}}_{3}\mathrm{Au}(001)$ due to the deposited alternate magnetic Fe and Co monolayers were studied. To observe the tuning mechanism, the spin density of the $\mathrm{FeCo}/{\mathrm{Cu}}_{3}\mathrm{Au}(001)$ as a function of the number of deposited magnetic monolayers was extensively investigated. The Fe/Co deposition induces a hybridization between electronic states of the magnetic and nonmagnetic interface atoms, generating a broadening in $d$ bands of the deposited material, engineering the magnetic moments of the interface atoms. This observed hybridization elucidates the charge variation in the interface atoms for stacking sequences starting with Fe or with Co as the first magnetic layer in direct contact with the ${\mathrm{Cu}}_{3}\mathrm{Au}(001)$ substrate. By performing the spin-charge density calculations, we demonstrated that this magnetic induction occurs only for the nonmagnetic Cu-Au atoms at the ${\mathrm{Cu}}_{3}\mathrm{Au}(001)$ surface.

LEED I(E) analysis of pseudomorphic Fe(111) monolayer on Ru(0001) surface and oxygen adsorption structure

LEED I(E) analysis of pseudomorphic Fe(111) monolayer on Ru(0001) surface and oxygen adsorption structure

Correlation of Magnetism and Disordered Shiba Bands in Fe Monolayer Islands on Nb(110).

Two-dimensional (2D) magnet–superconductor hybrid systems are intensively studied due to their potential for the realization of 2D topological superconductors with Majorana edge modes. It is theoretically predicted that this quantum state is ubiquitous in spin–orbit-coupled ferromagnetic or skyrmionic 2D spin–lattices in proximity to an s-wave superconductor. However, recent examples suggest that the requirements for topological superconductivity are complicated by the multiorbital nature of the magnetic components and disorder effects. Here, we investigate Fe monolayer islands grown on a surface of the s-wave superconductor with the largest gap of all elemental superconductors, Nb, with respect to magnetism and superconductivity using spin-resolved scanning tunneling spectroscopy. We find three types of islands which differ by their reconstruction inducing disorder, the magnetism and the subgap electronic states. All three types are ferromagnetic with different coercive fields, indicating diverse exchange and anisotropy energies. On all three islands, there is finite spectral weight throughout the substrate’s energy gap at the expense of the coherence peak intensity, indicating the formation of Shiba bands overlapping with the Fermi energy. A strong lateral variation of the spectral weight of the Shiba bands signifies substantial disorder on the order of the substrate’s pairing energy with a length scale of the period of the three different reconstructions. There are neither signs of topological gaps within these bands nor of any kind of edge modes. Our work illustrates that a reconstructed growth mode of magnetic layers on superconducting surfaces is detrimental for the formation of 2D topological superconductivity.

Unraveling the Catalytic Performance of the Nonprecious Metal Single-Atom-Embedded Graphitic s-Triazine-Based C3N4 for CO2 Hydrogenation.

Graphitic carbon nitride (g-C3N4) is regarded as a promising potent photoelectrocatalyst for CO2 reduction. Here, extensive first-principles calculations and ab initio molecular dynamics (AIMD) simulations are performed to systematically explore the structural and electronic properties of nonprecious metal single-atom-embedded graphitic s-triazine-based C3N4 (M@gt-C3N4, M = Mn, Fe, Co, Ni, Cu, and Mo) monolayer materials and their catalytic performances as the single-atom catalysts (SACs) for CO2 hydrogenation to HCOOH, CO, and CH3OH. It is found that the atomically dispersed non-noble metal Mn, Fe, Co, and Mo sites anchored on gt-C3N4 can efficiently activate both H2 and CO2, and their coadsorbed state serves as a precursor to the hydrogenation of CO2 to different C1 products. Among these SACs (M@gt-C3N4, M = Mn, Fe, Co, and Mo), Co@gt-C3N4 was predicted to have the best catalytic performance for CO2 hydrogenation to C1 products, although their mechanistic details are somewhat different. The predicted energy barriers of the rate-determining steps for the conversion of CO2 into HCOOH, CO, and CH3OH on Co@gt-C3N4 are 0.58, 0.67, and 1.19 eV, respectively. The desorption of products is generally energy-demanding, but it can be facilitated remarkably by the subsequent adsorption of H2, which regenerates M@gt-C3N4 for the next catalytic cycle. The present study demonstrates that the catalytic performance of gt-C3N4 can be well regulated by embedding the non-noble metal single atom, and the porous gt-C3N4 is nicely suited for the construction of high-performance single-atom catalysts.

Stepping Beyond Cyclic Voltammetry: Obtaining the Electronic Properties of Electrified Solid-Liquid Interfaces

Organically tailorable monolayers of ferrocene-terminated alkanethiol self-assembled monolayers (Fc SAM, Fig. 1a) on Au surfaces are attractive model systems to elucidate the molecular-level physicochemical properties of solid-liquid electrochemical (EC) interfaces [1]. In particular, Fc SAM has been shown to be an attractive spectroscopic molecular probe for photoelectron spectroscopy because the Fe heteroatom is at a fixed position above the electrode surface. Thus, this allows photoelectron spectroscopy to ascertain the electronic and structural properties at a fixed position above the electrode surface [2-3]. The ability to obtain molecular-level structure-function-property relationships with Fc SAM has relevance to bio(chemical) sensors, micro-actuators, and molecular electronics.Here, we use X-ray and ultraviolet photoelectron spectroscopy combined with an electrochemical cell (EC-XPS/UPS) to electrochemically control the Fc SAM and spectroscopically probe the corresponding electronic and structural changes [2-3]. To perform our experiments, electrochemical (EC) measurements are performed in a separate and dedicated EC chamber in a solution environment under Ar atmosphere, followed by evacuation and finally transfer to the XPS/UPS analysis chamber [2-3]. The EC chamber contains a retractable PTFE (polytetrafluorethylene) cell and utilizes a hanging meniscus setup. I will discuss the merits and challenges of EC-XPS/UPS methodology in the context of other approaches.Using EC-XPS/UPS, we are able to discriminate anion dependencies (Fig. 1b-d) with respect to the Fe oxidation state, monolayer thickness, and changes to the valence structure regarding the highest occupied molecular orbital (HOMO. Lastly, we are able to spectroscopically probe the changes relating to the interfacial potential distribution across the electrode-monolayer-electrolyte interface or so-called “potential drop” in the form of systematic potential-induced binding energy shifts in the XPS/UPS spectra. Further details will be provided at the presentation. Fig. 1 (a) Ferrocene-terminated alkanethiol SAM on Au. Schematic of electrode-monolayer-electrolyte interface and interfacial potential distribution. (b) Cyclic voltammograms at 50 mV s-1 in 0.1 M NaTFSI or NaPF6 (c-d) Fe 2p3/2 spectra of Fc SAM, pristine and after anodic/cathodic polarization at 0.625 and 0 V, respectively.

Electric field control of magnons in magnetic thin films: Ab initio predictions for two-dimensional metallic heterostructures

We explore possibilities for control of magnons in two-dimensional heterostructures by an external electric field acting across a dielectric barrier. By performing ab-initio calculations for a Fe monolayer and a Fe bilayer, both suspended in vacuum and deposited on Cu(001), we demonstrate that external electric field can significantly modify magnon lifetimes and that these changes can be related to field-induced changes in the layer-resolved Bloch spectral functions. For systems with more magnon dispersion branches, the gap between high- and low-energy eigenmodes varies with the external field. These effects are strongly influenced by the substrate. Considerable variability in how the magnon spectra are sensitive to the external electric field can be expected, depending on the substrate and on the thickness of the magnetic layer.

Adsorption of Ru2O4 on Fe, Ni, Co, and Cu-doped MoS2 monolayer and effect of applied electric field: A DFT study

Aiming at the problem of adsorption of Ru2O4 due to the intrinsic monolayer MoS2 nanomaterials, the method of substituting Fe, Ni, Co, and Cu atoms to dope sulfur atoms on the surface of the material is used to improve the inherent defect of no dangling bonds on the surface of the material. Through the calculation of the formation energy and electronic structure of the substrate, the improvement of the conductivity of the material was found and the operability of the doping treatment experiment was confirmed. The results of the adsorption calculation of gas molecules on its surface show that the gas sensing performance of the material has been greatly improved, especially for Ru2O4 molecules, the adsorption energy reaches −3.05 eV, the electron transfer increases to 0.22 e, and the adsorption length decreases to 2.4 Å, which proves that the material has good selectivity to Ru2O4.

DFT+Σ2 method for electron correlation effects at transition metal surfaces

We present a computational approach for electronically correlated metallic surfaces and interfaces, which combines Density Functional and Dynamical Mean Field Theory using a multi-orbital perturbative solver for the many-body problem. Our implementation is designed to describe ferromagnetic metallic thin films on a substrate. The performances are assessed in detail for a Fe monolayer on a W(110) substrate, a prototypical nanoscale magnetic system. Comparing our results to photoemission data, we find qualitative and quantitative improvements in the calculated spectral function with respect to the results of Density Functional Theory within the local spin density approximation. In particular, the spin-splitting of the $d$ states is drastically reduced and, at the same time, their spectral width becomes narrower. The method is therefore able to account for the main correlation effects in the system.

Tuning Ferromagnetism in a Single Layer of Fe above Room Temperature.

The crystallographic and magnetic properties of an Fe monolayer (ML) grown on 2 ML Au/W(110) substrate are studied with spin-polarized low-energy electron microscopy, density functional theory, and relativistic screened Korringa–Kohn–Rostoker calculations. The single layer of iron atoms possesses hexagonal symmetry and reveals a ferromagnetic order at room temperature. We experimentally demonstrate the possibility of tuning the Curie temperature and the magnitude of magnetization of the Fe monolayer by capping with Au. Taking into account several structural models, the calculation results mostly show ferromagnetic states with enhanced magnetic moments of Fe atoms compared to their bulk value and a further increase in their value after covering with Au. The theoretically calculated Curie temperatures are in fair agreement with those obtained in the experiments. The calculations, furthermore, found evidence for the presence of frustrated isotropic Fe–Fe exchange interactions, and a discussion of the structural effects on the magnetic properties is provided herein.

Exploring room-temperature ferromagnetism in WXBC (X = W, Mn, Fe) monolayers.

Two-dimensional (2D) transition metal boron-carbide is a novel material that has unique properties suitable for advanced spintronics and storage applications. Through first-principles calculations based on density functional theory (DFT) calculations, we report a new class of stable 2D ceramic WXBC (X = W, Mn, Fe) monolayers. We find that all WXBC monolayers prefer a ferromagnetic ground state with metallic electronic property. DFT calculations proved that WXBC monolayers exhibit good energetic, mechanical, and dynamic stabilities. More importantly, these monolayers exhibit large magnetic anisotropy energy (MAE) of 1213 μeV, 247 μeV and 20 μeV per magnetic atom for W2BC, WMnBC, and WFeBC, respectively. An out-of-plane easy axis (EA) magnetization direction is found for W2BC whereas the EA for WMnBC and WFeBC are in-plane. By performing Monte Carlo (MC) simulations based on the 2D Heisenberg model, we predict Curie temperatures (T C) of 155 K for the W2BC monolayer. The Berezinskii-Kosterlitz-Thouless transition (BKT) temperature values of WMnBC and WFeBC are as high as 374.69 K and 417.39 K. For further investigations, the adsorption properties of Li, Na, and K atoms on WXBC (atm-WXBC) systems are examined. It is revealed that the initial ferromagnetic metallic properties of bare WXBC monolayers are maintained for all atm-WXBC systems. The obtained strong chemisorption energies are high enough to make adsorbed Li, Na, and K immobile on WXBC surfaces. All these findings demonstrate the unique potential of WXBC monolayers as multifunctional candidates for advanced magnetic device and storage applications.

First-principle calculations of the magnetic anisotropy of Fe and Co films separated by an interlayer of non-magnetic metals

This paper presents the results of numerical calculations of the magnetic characteristics of Co and Fe monolayer films on Cu and Pt surfaces using the VASP software package. The values of the difference between the total energies of the antiferromagnetic and ferromagnetic configurations are calculated depending on the convergence parameters and the thickness of the nonmagnetic material. The values of the magnetic anisotropy and magnetic moment of atoms in the structures of Co/Cu/Co, Fe/Pt/Fe, Co/Pt/Co, Pt/Co/Cu/Co/Pt are determined depending on the orientation of the surface face. For the (110) and (111) faces, the phenomenon of reorientation in the Co/Cu/Co structure is confirmed, when the anisotropy of the cobalt films parallel to the surface plane is replaced by the perpendicular anisotropy due to the introduction of an ultrathin platinum film into the structure. Keywords: Magnetic anisotropy, ultrathin magnetic films.

Perpendicular Magnetic Anisotropy and Its Electric Field Manipulation in Magnetic Multilayered Heterostructures

"Understanding of underlying physics related to the Perpendicular Magnetic Anisotropy (PMA) in magnetic heterostructures represents a major issue for its exploit in random-access memory (MRAM) devices. Using ab-initio analysis, we reveal some basic aspects related to the anatomy of PMA and its variation with electric field in various X/Fe/MgO(001) multilayer configurations (X=Cr, Au, V, Ag, Pt, Pd,…) compatible with standard experimental architectures of magnetic tunnel junction devices. Our study quantifies and underlines the significant role of the Rashba interfacial field on PMA. We explain and correlate the sign, the magnitude, and the electric field dependence of the PMA, the Rashba coefficient R and the Dzyaloshinskii–Moriya (DMI) asymmetric exchange interaction parameter. Moreover, when varying the Fe thickness in X/Fe/MgO(001) systems, we observe oscillations of PMA with the number of Fe monolayers, explained within the framework of quantum wells of the 1 Bloch symmetry electrons in Fe. Further atomistic micromagnetic simulations including different Fe layer thicknesses and the corresponding PMA predict macroscopic magnetization characteristics in realistic experimental systems. Keywords: perpendicular magnetic anisotropy, electric field control of PMA, magnetic tunnel junctions, magnetic multilayer heterostructures, atomistic magnetic simulations. "