Total Magnetic Moment Research Articles

Effect of Cu doping on the electronic structure, magnetic and optical properties of GaN/ZnS heterojunctions: a first-principles study

In this paper, the generalized gradient approximation method in density functional theory is adopted to calculate the GaN/ZnS heterojunction system with coexistence of Cu doping and point defects. The electronic structure, magnetic coupling mechanism and optical properties of each system are analyzed. It is shown by the research results that broader band gap width tuning (0.26–2.92 eV) can be achieved in the interface region of the Cu-doped GaN/ZnS heterojunction system. The magnetic sources of the system have two aspects, on the one hand, unpaired electrons are induced by cation vacancies to undergo spin polarization, thereby magnetic moments are contributed to the system, on the other hand, The GaN/ZnS heterojunction is induced by Cu doping to generate bound magnetic polarons, causing a magnetic phase transition in the system, and the total magnetic moment of the system is restricted by the concentration of bound magnetic polarons. In terms of optical properties, deep energy levels are introduced and hole-electron recombination centers are formed in the Cu-doped heterojunction system containing Ga vacancies. Compared with the non-magnetic heterojunction system, the magnetic heterojunction system exhibits a higher absorption intensity for visible light, and the redshift of its absorption spectrum is more pronounced. Furthermore, when the Cu-doped GaN/ZnS heterojunction system contains different vacancy defects, different conductive types can be achieved.

Charge doping and electric field tunable ferromagnetism and Curie temperature of the MnS2 monolayer.

Two-dimensional ferromagnets with a long-range ferromagnetic ordering at finite temperature present a bright prospect for their potential applications in nanoscale spintronic devices. The tuning of their intrinsic ferromagnetism and Curie temperature is essential for the development of next-generation data storage and spintronic devices. In this work, the electronic structures, ferromagnetism and Curie temperature of two-dimensional MnS2 monolayer are controlled by charge doping and electric field using first principles calculations. The results show that the dynamic and thermal stability of monolayer MnS2 for all of the cases can be still maintained. Moreover, there is no existence of phase transition and all MnS2 monolayers at any charge doping concentrations and electric field intensities favor ferromagnetic coupling. For the manipulation of electron doping, the calculated total magnetic moment Mtot of the MnS2 monolayer exhibits an increase from 3.112 to 3.491μB per unit cell. Further analysis indicates that a transition from half-metal to metal occurs by introducing the charge doping and vertical electric field, and the Mn 3d electronic states are the major determinants of ferromagnetism. Additionally, the charge doping enables the magnetic anisotropy energy to transform from an in-plane easy axis to the magnetization direction out of the plane. The Curie temperature Tc of the MnS2 monolayer can be moderately enhanced above room temperature by hole doping and application of a vertical electric field. Remarkably, Tc reaches its peak at 767 K at a hole doping concentration of -0.8e. This work enriches the microscopic understanding of the tuning mechanism of ferromagnetism and supplies a sound theoretical basis for subsequent experimental studies.

Origin of the Magnetic-Optical Properties of Palladium Compounds, an Ab Intio Study

Abstract: The structural, magnetic, and magneto-optical properties of the PdM (M=Fe, Co, Ni) alloy are investigated using first-principles calculations with the exciting code. The study employs the full potential linearized augmented plane wave method (FP-LAPW) based on density functional theory (DFT). The exchange-correlation energy is described in the generalized gradient approximation developed by Perdew-Burke-Ernzerhof (PBE-GGA). The calculated lattice parameters are in good agreement with theoretical and experimental results. The magnetic properties reveal a ferromagnetic stability phase for all compounds. Additionally, the total (TDOS) and partial (PDOS) density of states, along with the band structure, indicate that PdM (M = Fe, Co, Ni) exhibits metallic behavior. The total and local magnetic moments are investigated. We conducted a study on the polar magneto-optical Kerr effect and calculated Kerr spectra. The microscopic origins of the peaks found in Kerr's angle are interpreted as interband transitions, primarily arising from the states (d to d) in the PdNi and (S to d) in the PdFe and PdCo alloys. Keywords: P-MOKE, DFT, GGA-PBE, Intermetallic.

Doping effect on electronic and magnetic properties of Ag-doped single-walled (6,0) GaN nanotubes: First-principles study

The electronic and magnetic properties of GaN wurtzite, un-doped, and Ag-doped single-walled (6,0) chiral GaN nanotubes (SWGaNNT) were investigated using Density Functional Theory and Local Spin Density Approximation methods within Hubbard U semiempirical correction (DFT-LSDA + U). In a consecutive DFT-LSDA + U electronic structure simulation, the effects of defects on the nature and origin of ferromagnetism (FM) are studied for an Ag-doped SWGaNNT system. For the Ag-doped GaN nanotube configurations, the energy gap decreases with increasing concentration of impurity. The total energy calculations for doped systems show the stability of the ferromagnetic phase. In the case of the Ag-doping GaN NT system, the wide energy gap is decreasing and the total magnetic moment of this system is ∼2.0 μB. From first-principles calculations, an Ag-doped GaN nanosystem can be made into a magnetic ferromagnetic material, and it is an important candidate for spintronics device applications.

Theoretical Investigations of the Structural, Dynamical, Electronic, Magnetic, and Thermoelectric Properties of CoMRhSi (M = Cr, Mn) Quaternary Heusler Alloys

The structural, dynamical, electrical, magnetic, and thermoelectric properties of CoMRhSi (M = Cr, Mn) quaternary Heusler alloys (QHAs) were investigated using density functional theory (DFT). The Y-type-II crystal structure was found to be the most stable configuration for these QHAs. Both CoCrRhSi and CoMnRhSi alloys possess a half-metallic behavior with a 100% spin-polarization as the majority spin channel is metallic. On the other hand, the minority spin channel is semiconducting with narrow indirect band gaps of 0.54 eV and 0.57 eV, respectively, along the Γ−X high symmetry line. In addition, both CoCrRhSi and CoMnRhSi alloys possess a ferromagnetic structure with total magnetic moments of 4 μB, and 5 μB, respectively, which are prominent for spintronics applications. The thermoelectric properties of the subject QHAs were calculated by using Boltzmann transport theory within the constant relaxation time approximation. The lattice thermal conductivities were also evaluated by Slack’s equation. The predicted values of the figure-of-merit (ZT) for CoCrRhSi and CoMnRhSi were found to be 0.84 and 2.04 at 800 K, respectively, making them ideal candidates for thermoelectric applications.

A comparative study of physical and thermoelectrical characteristics of the new full‐Heusler alloys Ag2TiGa and Ag2VGa with ab initio calculations

AbstractThis paper will focus on the comparative study of the structural, electronic, magnetic, optical, and thermoelectric properties of the two Heusler systems Ag2TiGa and Ag2VGa in the inverse L21 Hg2CuTi structure. Using the density functional theory‐based wien2k code, which implements the computational methods used in this study, namely GGA, GGA‐mBJ, GGA + U, and GGA + SOC (spin‐orbit coupling). The band structures show that all two structures studied are metallic. The spin density of states of Ag2VGa has evident spin splitting near the Fermi level, and the total magnetic moment of the Ag2VGa structure is 2.19 μB, which indicates that Ag2VGa is magnetic. The full‐Heusler Ag2VGa material can be used as spintronic materials due to their high spin polarization (about 50%). While Ag2TiGa has low polarization so it is bad electronically, but better thermoelectrically than Ag2VGa. So, the full‐Heusler Ag2TiGa material may also be considered as a potential candidate for thermoelectric applications at room temperature. Studies of the two new Heusler alloys may provide a theoretical reference for subsequent theoretical research and experimental synthesis of Ag‐based Heusler alloys.

Defective ZrSe2: a promising candidate for spintronics applications

The current study presents the electronic and magnetic properties of monolayer ZrSe2 nanoribbons. The impact of various point defects in the form of Zr or Se vacancies, and their combinations, on the nanoribbon electronic and magnetic properties are investigated using density functional theory calculations in hydrogen-terminated zigzag and armchair ZrSe2 nanoribbons. Although pristine ZrSe2 is non-magnetic, all the defective ZrSe2 structures exhibit ferromagnetic behavior. Our calculated results also show that the Zr and Se vacancy defects alter the total spin magnetic moment with D6Se, leading to a significant amount of 6.34 µB in the zigzag nanoribbon, while the largest magnetic moment of 5.52 µB is induced by D2Se−2 in the armchair structure, with the spin density predominantly distributed around the Zr atoms near the defect sites. Further, the impact of defects on the performance of the ZrSe2 nanoribbon-based devices is investigated. Our carrier transport calculations reveal spin-polarized current-voltage characteristics for both the zigzag and armchair devices, revealing negative differential resistance (NDR) feature. Moreover, the current level in the zigzag-based nanoribbon devices is ∼10 times higher than the armchair devices, while the peak-to-valley ratio is more pronounced in the armchair-based nanoribbon devices. It is also noted that defects increase the current level in the zigzag devices while they lead to multiple NDR peaks with rather negligible change in the current level in the armchair devices. Our results on the defective ZrSe2 structures, as opposed to the pristine ones that are previously studied, provide insight into ZrSe2 material and device properties as a promising nanomaterial for spintronics applications and can be considered as practical guidance to experimental work.

Influence of main-group elements on structural, electronic, magnetic and half-metallic properties of DO3-type Mn3Z (Z = Al, Ga, In, Si, Ge, Sn, P, As and Sb) alloys - A DFT study

We investigate the influence of main-group elements belonging to group III (Al, Ga and In), IV (Si, Ge and Sn) and V (P, As and Sb) on structural, electronic, magnetic and half-metallic (HM) properties of DO3-type Mn3Z alloys using density functional theory (DFT). In particular, we emphasize on the correlation between structural parameters (lattice constant) and the changes in electronic and magnetic properties of Mn3Z alloys. From full geometry optimization results, we find that the entire Mn3Z alloys stabilized to ferrimagnetic ordering. Further, the spin-polarized density of states (DOS) calculation reveals that Mn3Z (Z = Al, Si, Ge, Sn, As and Sb), Mn3Ga and Mn3In alloys exhibit, respectively, half-metallic (HM), nearly half-metallic (NHM) and metallic nature. While, the Mn3P alloy displays spin-gapless semiconducting (SGS) feature, in which spin-up and spin-down channels show metallic and spin-gapless feature, respectively. The Mn3Al, Mn3Z (Z = Si, Ge and Sn) and Mn3Z (Z = P, As and Sb) alloys follow Slater-Pauling rule well, and gives 100 % spin-polarization at the Fermi energy (EF) with total integer magnetic moment of 0, 1 and 2 μB/f.u, respectively. The contribution to total magnetic moment in all the Mn3Z alloys comes predominantly from Mn(Y) atoms. The molecular orbital (MO) hybridization mechanism is proposed to rationalize the HM band gap.

An Ab-initio study on spin gapless semiconducting in novel quaternary heusler alloys RhCoVZ (Z = Al, Ga, and In): Insights into stability, electronic, magnetic, thermoelectric, and optical properties

The stability and half-metallic ferromagnetic properties of recently developed gapless semiconductor alloys, RhCoVZ (Z = Al, Ga, and In), were the subject of investigation in this research study. Three different non-equivalent structural configurations, namely type I, type II, and type III structures, have been examined. Among these compounds, Type I is characterized as the most stable phase in the ferromagnetic order, as opposed to the non-magnetic order. Through calculations of cohesive energies, formation energies, phonon dispersion curves, and elastic constants, we have demonstrated that RhCoVZ (Z = Al, Ga, and In) exhibits thermodynamic stability, as well as dynamic and mechanical. Using modified Becke-Johnson (mBJ) calculations, it has been revealed that RhCoVZ (Z = Al, Ga, and In) are spin gapless semiconductor half-metallic ferromagnets with an indirect bandgap. Additionally, it was observed that the electrons at the Fermi level (EF) are entirely spin-polarized. The total magnetic moment in all three compounds was determined to be an integer value of 2.00 µB per formula, in accordance with the Slater-Pauling rule (Mt = Zt - 24). All the calculations in this study were performed using density functional theory (DFT) based on the full-potential linearized augmented plane wave (FP-LAPW) method, which was implemented in the WIEN2k code. The effective mass of electrons/holes is (0.167/0.385) for RhCoVAl, (0.454/0.322) for RhCoVGa, and (0.604/0.242) for RhCoVIn. The thermoelectric properties of the three compounds were explored using the semi-classical Boltzmann transport theory. It was discovered that all three compounds exhibit high power factors and high Seebeck coefficients, with values reaching up to 1.5 mV/K for RhCoVAl and 1.25 mV/K for RhCoVGa. Based on the results, the highest observed ZT values for RhCoVZ (Z = Al, Ga, and In) are 0.95, 0.97, and 0.93, respectively. The study's findings indicate that these compounds possess stable characteristics, making them promising candidates for various device applications in fields like spintronics, thermoelectricity, shape memory, and spin filters. Furthermore, the investigation of their optical properties, including the dielectric function and absorption coefficient, suggests potential implications for optoelectronic applications. Overall, these materials exhibit diverse and valuable properties, opening up exciting opportunities for future technological advancements in multiple domains.

Electronic structure and magnetic properties of CrI3 monolayer doped by rare earth metal atoms

CrI3 monolayer is a two-dimensional (2D) ferromagnetic (FM) semiconductor materials with broad application prospects in the field of spintronics due to its magnetic semiconductor feature and unique 2D structure. In this work, we employ first-principles calculations based on density functional theory to investigate the electronic structure and magnetic properties of CrI3 monolayer doped with rare earth (RE) metal atoms (RE = Sc, Y, La, Ce, Pr, Nd, Pm, Eu, Gd, Tm, and Lu). The results demonstrate that doping with RE atoms enables the control of total magnetic moments and a significantly enhancement of the Curie temperature of CrI3 monolayer. Especially, the Curie temperature of CrGdI6 monolayer reaches 347.58 K, which could be a promising candidate for realizing room temperature ferromagnetism. Furthermore, by applying strain and electric field, the CrREI6 monolayers exhibit metal, half-metal and spin gapless semiconductor properties. These findings not only provide valuable insights into the manipulation of electronic structure and magnetic properties in CrI3 monolayer but also establish RE doped CrI3 monolayer as a promising material for spintronic devices.

First-principles calculations to investigate Structural, mechanical, electronic, magnetic and thermoelectric properties of MRh2O4 (M = Mg, Mn, Cd) spinel oxides

Structural, mechanical, magnetic, electronic and thermoelectric properties of MRh2O4 (M = Mg, Mn, Cd) spinel oxides are studied through first-principles calculations. Calculations of structural and elastic stiffness constants (Cij’s) show that the MRh2O4 oxides are stable structurally and mechanically. Elastomechanical results show that the CdRh2O4 is ductile, MnRh2O4 is brittle, while MgRh2O4 lies on the borderline differentiating the ductile and brittle character. MnRh2O4 has high bulk modulus and high Young’s modulus which indicate its ability to resist plastic deformation. MnRh2O4 spinel oxide bears the highest values of Debye temperature (TD = 634.4 K) and melting temperature (Tm = 3530.4 K) among the MRh2O4 (M = Mg, Mn, Cd) oxides. Band structure calculations and density of states spectra indicate the p-type semiconducting nature of MRh2O4 (M = Mg, Mn, Cd) oxides. Spin-polarized electronic structure of CdRh2O4 show 100 % spin-polarized behavior, while MgRh2O4 and MnRh2O4 oxides show 0.12 % and 0.29 % spin-polarization, respectively. MnRh2O4 exhibits saturation magnetization Ms = 172 emu/g and total magnetic moment mtot = 9.99 µB/f.u. Temperature dependent thermoelectric properties (thermal conductivity, electrical conductivity, Seebeck coefficient, Hall coefficient, power factor and figure of merit) are also studied for MRh2O4 oxides. Calculated thermoelectric properties of MRh2O4 (M = Mg, Mn, Cd) oxides show that these oxides are promising for applications as novel thermoelectric materials.

High Spin Magnetic Moments in All-3d-Metallic Co-Based Full Heusler Compounds.

We conduct ab-initio electronic structure calculations to explore a novel category of magnetic Heusler compounds, comprising solely 3d transition metal atoms and characterized by high spin magnetic moments. Specifically, we focus on Co2YZ Heusler compounds, where Y and Z represent transition metal atoms such that the order of the valence is Co > Y > Z. We show that these compounds exhibit a distinctive region of very low density of minority-spin states at the Fermi level when crystallizing in the L21 lattice structure. The existence of this pseudogap leads most of the studied compounds to a Slater-Pauling-type behavior of their total spin magnetic moment. Co2FeMn is the compound that presents the largest total spin magnetic moment in the unit cell reaching a very large value of 9 μB. Our findings suggest that these compounds are exceptionally promising materials for applications in the realms of spintronics and magnetoelectronics.

Tuning the magnetic properties of doped ZnS using transition metal doping: A multi-scale computational approach

Transition metal (TM)-doped dilute magnetic semiconductors (DMS) have emerged as promising materials for spintronic applications such as spin-polarized transport and information storage. However, achieving robust room-temperature ferromagnetism in DMS remains a key challenge. This work undertakes a comprehensive investigation of the effects of Ti- and Cr-doping and (Ti,Cr)-codoping on the structural, electronic, and magnetic properties of wurtzite ZnS using first-principles pseudopotential plane-wave self-consistent field calculations and Monte Carlo simulations. The first-principles DFT calculations were performed using the spin-polarized GGA+U approach to account for strong electron–electron interactions. Structural relaxations revealed expanded lattice parameters and bond lengths for the doped systems compared to pure ZnS, attributed to the larger ionic radii of the dopants. Formation energy calculations confirmed the thermodynamic stability of doping. The band structure and density of states analysis demonstrated the half-metallic nature of the doped ZnS systems with 100% spin polarization induced by strong hybridization between the TM-3d and S-3p states. This mediates robust ferromagnetic coupling, with total magnetic moments around 4-8 μB/cell depending on dopant type and concentration. To complement the zero-temperature DFT results, temperature-dependent Monte Carlo simulations using the single-spin flip Heat Bath algorithm were implemented. The modeling of magnetization, susceptibility, specific heat, and hysteresis loops enabled extracting Curie temperatures up to 427.6 K for 12.5% Cr-doped ZnS. The synergistic combination of first-principles DFT and Monte Carlo computational techniques provides significant insights into tailoring the magnetic properties of TM-doped ZnS dilute magnetic semiconductors. The tunability of structural, electronic, and magnetic characteristics through control of dopant selection and concentration demonstrates the promising potential of transition metal-doped ZnS for spintronic devices operable at room-temperature.

First-principle study of Mg-based rare earth spinels MgSm2Y4 (Y[dbnd]S, Se) for spintronic and thermoelectric devices

Mechanical, spin-polarized electronic, and transport characteristics of rare-earth-based MgSm2Y4 (YS, Se) spinels are investigated using first-principle calculations. In contrast to the anti-ferromagnetic and nonmagnetic states of MgSm2Y4 (YS, Se), the optimization study reveals that ferromagnetic states release more energy, and optimized lattice constants in ferromagnetic states are comparable to existing values. Phonon dispersion and formation energy are also calculated to confirm the dynamical stability stability. The ductile character is confirmed by investigating the Poisson's and Pugh ratios, and the values of other elastic parameters show their importance for the manufacturing of devices. Heisenberg model and the density of electron states at the Fermi level report the Curie temperature and the spin polarization. Spin-polarized electronic properties indicate half-metallic ferromagnetic because the spin-down reflects a semiconductor nature, whereas the metallic nature manifests the spin-up. The total magnetic moments are generated through hybridization of chalcogenide 2p-states and the Sm f-states. We found that the studied spinels may be used in thermoelectric devices by examining transport characteristics such as electronic and phononic thermal conductivity, Seebeck co-efficient, and figures of merit (ZT). Our results indicate that the ZT for MgSm2S4 is almost three times the ZT obtained for MgSm2Se4.

Insights into structural, electronic, optical properties, and impedance spectroscopy of semi-doped perovskite Nd0.5Ba0.5CoO3: A theoretical and experimental study

In this study, the electronic, structural, and optical properties of semi-doped perovskite Nd0.5Ba0.5CoO3 (NBCO) were investigate using the CASTEP software, which relies on density functional theory (DFT) along with the correlation function of generalized gradient approximation (GGA) and Perdew-Burke-Ernzerhof (PBE). The mesh parameters of the (super) cell indicate that NBCO adopts an orthorhombic structure in the Pmmm space group, featuring a Coulomb Energy (EC) of approximately −244 eV. DFT and total density of states (DOS) analyses reveal that the as-prepared perovskite manifests metallic characteristics, and a notable covalent interaction is observed between the O-p and Co-d spin states, indicating strong hybridization between these orbitals. Remarkably, NBCO demonstrates 100 % spin polarization (P) at the Fermi level, with a calculated total magnetic moment of approximately 3.44 μB. Moreover, low dielectric loss (tgδ) values suggest facile electron movement, and impedance spectroscopy illustrates a dielectric relaxation phenomenon. DFT calculations predict an orthorhombic crystal structure with higher electron density at cobalt atom positions. Band structure and DOS analyses affirm metallic behavior owing to the robust hybridization between oxygen-p and cobalt-d orbitals. Optical property assessments reveal potential applications in spintronics and optoelectronics, with notable absorption in the ultraviolet–visible range. The conductivity spectra from impedance spectroscopy contribute to understanding temperature-dependent charge transport mechanisms. Dielectric constants decrease with increasing frequency and temperature, while dielectric losses remain low, indicating efficient electron movement. The material adheres to a metallic conduction mechanism as described by Drude's law, and the material's 100 % spin polarization at the Fermi level and a total magnetic moment of 3.44 μB are significant findings. Negative dielectric constants observed at specific frequencies suggest potential applications in metamaterials. Overall, the determined properties position NBCO cobaltite as a promising candidate for high-frequency devices, spintronic components, and sensors.

Machine learning driven prediction of lattice constants in transition metal dichalcogenides

Machine learning represents an emerging branch of artificial intelligence, centering on the enhancement of algorithms in computer programs through the utilization of data and the accumulation of research-driven knowledge. The requirement for artificial intelligence in materials science is essential due to the significant need for innovative high-performance materials on a large scale. In this report, the gradient boosting regression tree model of machine learning was applied to predict the lattice constants of cubic and trigonal MX2 systems (M=transition metal and X=chalcogen atoms). The theoretical/experimental values of the materials were compared to the predicted values to calculate the standard errors such as RMSE (root mean square error) and MAE (mean absolute error). The features used to predict lattice constants were ionic radius, lattice angles, bandgap, formation energy, total magnetic moment, density and oxidation states. The features versus contribution barplot has been drawn to reveal the contribution level of each parameter in the degree of [0,1] to obtain the predictions. This report provides a precise account of the prediction methodology for lattice parameters of the transition metal dichalcogenides family, a process that was previously not reported.

Study of ferromagnetism, and thermoelectric behavior of double perovskites K2Z(Cl/Br)6 (Z = Ta, W, Re) for spintronic, and energy application

Spintronic is the developing technology which probes the properties of quantum devices with spin of electrons which reduce the size and enhance its speed. Therefore, here the role of 5d electrons and thermoelectric characteristics of double perovskites (DPs) K2ZCl/Br6 (Z = Ta, W, Re) elaborated comprehensively by density functional theory (DFT). The Heisenberg model spin polarization density (SP) has been applied to evaluate the Curie temperature (Tc) and spin polarization factor. The tolerance factor (tF) and formation energy (ΔH) have been calculated to confirm the stability of structures. Ferromagnetism has been discussed in terms of spin polarization, crystal field energy (ΔCF) and exchange energies (Δ(d), Δ(pd)). The double exchange mechanism, and exchange constants ensure the role of electrons spin in ferromagnetism instead of segregation of transition metal ions. The transferring of magnetic moments of transitions metals to nonmagnetic sites (K, Cl, Br) show the exchange of spin of electrons and integer values of total magnetic moment show 100 % spin polarization. Finally, the transport properties are studied in standings of electrical and thermal conductivities. The large value of Seebeck coefficient and power factor ensure the importance of studied DPs for thermoelectric generators.

A multiferroic coupling mechanism in the polar interface region of GaN-ZnO heterojunction: A first-principle study

In this paper, the electronic structure and ferroelectric-ferromagnetic coupling properties of Y-doped and vacancy-containing GaN-ZnO heterojunctions are systematically investigated by using the generalized gradient approximation + U (GGA + U) method within the framework of density functional theory. The results reveal that in systems with vacancy defects, the magnetism is generated by the spin polarization of unpaired electrons induced by cationic vacancies, and the magnetic moment of the system is related to the number of unpaired electrons. However, in systems containing interstitial Y-doping, the s-state and d-state electrons of the Y-doped elements are coupled by orbital hybridization to form bound magnetic polarons. Compared with the system containing vacancies, the bound magnetic polaron systems have better stability, although the magnetic moments are relatively small and the total magnetic moment is limited by the concentration of bound magnetic polarons. And the modulation of different magnetic changes can be achieved in different polar interfaces by adjusting the electric polarization intensity of the bound magnetic polaron systems.

Electronic, magnetic, half-Metallic, pressure-induced elastic and curie temperature predictions of Zr2RhTl Heusler alloy: DFT and EFT studies

ABSTRACT The DFT method investigated the total and partial magnetic moments, half-metallic characters, and pressure-dependent elastic properties of Zr2RhTl alloy. According to the ground state properties, the FM phase is more stable in energy than the AFM and NM phases. The Curie temperature value was obtained as 897.43 K with the help of the energy differences of the AFM and FM phases. The total magnetic moment of Zr2RhTl alloy was obtained as 2.00 µB/f.u. Partial magnetic moment values were obtained as 0.810, 0.506, 0.032, and 0.009 µB for Zr1, Zr2, Rh, and Tl atoms, respectively. All these total and partial magnetic moment values and Curie temperatures were supported by the Effective Field Theory (EFT) method. In addition, partial Curie temperatures of Zr2RhTl alloy were calculated by EFT separately for each element. The up-spins of Zr2RhTl alloy show metallic character in both the GGA and GGA + mBJ approximations, while the down-spins have band gaps of 0.698 and 0.699 eV, respectively. Electronic properties were also supported by GGA + U (U = 1, 2, 3 eV) interactions. Therefore, Zr2RhTl alloy is a true half-metallic ferromagnetic material. Zr2RhTl alloy was elastically stable, and the Debye temperature was calculated as 221.496 K at 0 GPa. All calculations obtained using two different methods (DFT and EFT) and two different approximations (GGA and GGA + mBJ) support each other. Therefore, Zr2RhTl alloy proved to be a very suitable material to be used as an alternative for spintronics.

Unveiling the Robust Struct-Electromagnetic Characteristics of CdAB2 Chalcopyrite (A = Cr, Mn, Fe; B = P, As): A Comprehensive Ab-Initio Study

We present a comprehensive investigation of the electromagnetic properties of CdAB2 compounds, where A represents Cr, Mn, or Fe, and B denotes P or As. To investigate the spin-polarized behavior of these compounds the A atoms were substituted at the Group IV (Ge) position in CdGeB2 in the chalcopyrite crystal structure. Our results reveal that all the CdAB2 compounds exhibit compelling spin-splitting of energy states near the Fermi level (EF). Notably, CdAB2 materials with A = Cr and Mn exhibit intriguing half-metallic ferromagnetic (HMF) characteristics, with the calculated total magnetic moments of 2.00 and 3.00 µB/f.u., respectively. The HMF properties originated in CdAB2 (A = Cr and Mn; B = P, As) these compounds owing to the hybridization of partially filled -3d(t2g) states of A atoms with the p-states of B (P, As) atoms, with minor contributions from Cd’s-like states. In contrast, CdFeB2 displays distinct behavior, demonstrating spin-splitting of energy levels around the EF indicative of a stable ferromagnetic (FM) state and the absence of HMF at their equilibrium volume. The calculated total magnetic moments for CdFeP2 and CdFeAs2 are about 1.83 (1.64 µB/f.u.) and 1.94 µB/f.u. (1.84 µB/f.u.) under generalized gradient approximation (GGA) (local spin density approximation (LSDA)) approximations, respectively. Perhaps these CdAB2 compounds (A = Cr and Mn; B = P, As) with HMF characteristic within both LSDA and GGA formalisms makes them highly promising candidates for spin injectors in the spintronic device applications. Furthermore, their semiconducting nature renders CdCrB2 and CdMnB2 materials compatible with silicon and other semiconducting lattices, enhancing their potential practical applications in the spintronic technologies. In conclusion, this study presents a thorough exploration of the robust electronic and magnetic properties of CdAB2 chalcopyrites, offering exciting prospects for their utilization in the future spintronic applications.