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Abstract In this paper, we investigated the magnetic properties of the cubic anti-perovskite Mn 3 CuN compound by applying the Monte Carlo simulation (MCs). The magnetism in this metallic Mn 3 CuN is provided by the Mn atoms (Mn4+)having the magnetic moment S = 1 and Cu (Cu2+) atoms described by the magnetic spin momentσ = 1/2. However, we presented and discussed the ground state phase diagrams where we observed the stable phases in different planes corresponding to different physical parameters of the system at zero absolute temperature T = 0 K. On the other hand, a model describing the system is proposed to solve the Hamiltonian governing the system. The results of the physical parameters such as the susceptibilities, magnetizations and the specific heat behaviors are deduced for the finite size, as a function of temperature. Moreover, the thermal behavior of the previous physical quantities with the variation of the exchange coupling interactions, the crystal field and the external magnetic field are presented and discussed. Also, the curves of the magnetizations as a function of the crystal field are plotted. Finally, the magnetic hysteresis loops of the studied system have been drawn. Highlights • We study the Anti-perovskite Metallic compound Mn 3 CuN. • We performed Monte Carlo simulations to investigate this model. • We outlined the exchange coupling interaction effect on the compensation temperature. • The magnetic properties of such system are presented and discussed. • The hysteresis loops are obtained and presented. [ABSTRACT FROM AUTHOR]

By using the molecular mean-field approach, a ferrimagnetic mixed spin square nanowire is dealt on the basis of Blume-Capel model. In this research paper, the core/shell structure is tested the effect of crystal fields and external magnetic fields on a ferrimagnetic mixed spin-1 and spin-7/2 square nanowire device, respectively. It is worth to note, spin-1 ions are located in the middle and in the corners of a rectangular plaquette there are four other spin-7/2 ions. One obtains a ferrimagnetic compensation behavior for the exchange interactions are modified with various crystal fields and different magnetic fields values. New features are found that the mixed spin square nanosystem has superparamagnetic behavior when D C / | J 1 | = 0.5 , − 0.5 , in the range − 1.0 ≤ D S / | J 1 | < − 0.2 , with K B T / | J 1 | = 0.75 , J 2 = − 1.0 , J 3 = − 0.75 , and J 1 = − 1.0 , respectively. • Molecular mean-field method (MMFM) has been used for the study of a ferrimagnetic mixed spin square Blume-Capel Ising nanowire consists of spin-1 and spin-7/2. • It has been investigated interesting phenomena are the behaviors of compensation, reentrance, and superparamagnetism, respectively. • The proposed system may exhibit more than two spin compensation points (i.e., many compensation temperatures), for certain negative values of ferrimagnetic crystal fields acting on the magnetic ions of both sublattices. • We report that the present nanosystem experiences superparamagnetism phenomenon when D C / | J 1 | = 0.5 , − 0.5 , i n t h e r a n g e − 1.0 ≤ D S / | J 1 | < − 0.2 , w i t h K B T / | J 1 | = 0.75 , J 2 = − 1.0 , J 3 = − 0.75 , a n d J 1 = − 1.0 , respectively. • The nanosystem experiences a jump which corresponds to the first-order transition obtain the phases are (-1, 3.5), (−1, 2.5), (−1, 1.5), (−1,0.5), when D C / | J 1 | = 0.0 , a n d D C / | J 1 | = − 1.0 f o r D S / | J 1 | = − 0.5 , D S / | J 1 | = − 0.55 , D S / | J 1 | = − 0.65 , o r − 0.75 , a n d D S / | J 1 | = − 1.0 , respectively. [ABSTRACT FROM AUTHOR]

The magnetic characteristics of a mixed graphyne lattice were analyzed using the Monte Carlo method with the Metropolis algorithm at both low and high temperatures. This study examines the impact of temperature, crystalline field, external magnetic field, and strong coupling interaction on magnetic characteristics. Our results demonstrate that the magnetization plateaus depend strongly on both low temperature and crystal field variation. The results are consistent with previous theoretical and experimental studies. The multiple magnetization plateaus of the mixed graphyne lattice can have potential applications in multi-state memories. • The magnetic characteristics of a graphyne lattice are studied using Monte Carlo simulations. • The study investigates the impact of t different parameters on magnetic characteristics. • The study examines the transition temperature of different parameters.. [ABSTRACT FROM AUTHOR]

It is predicted that the ZrCrCoZ(Z=B, Al, Ga, In) compounds with LiMnPbSn-type structure are half-metallic ferrimagnets with a large half-metallic gap by the first-principles calculations. The half-metallicity of the ZrCrCoZ(Z=B, Al, Ga, In) compounds are quite robust to the axial and uniaxial strain. The total magnetic moments in per unit cell are 4 μ B for the ZrCrCoZ(Z=B, Al, Ga, In) compounds and follow the Slater-Pauling rule, which can be attributed to the great spin-splitting. The calculated formation energies are negative for all the ZrCrCoZ(Z=B, Al, Ga, In) compounds, which indicates that those compounds are in the thermodynamic stability and the possibility of synthesis in experiment. [ABSTRACT FROM AUTHOR]

Significant magnetoreflection of unpolarized light in magnetostrictive ferrimagnetic single crystal of CoFe 2 O 4 has been revealed in the infrared spectral range. The magnetoreflection effect in CoFe 2 O 4 is up to 4% in a relatively small magnetic field. We experimentally demonstrate clear correlation between magnetostriction and magnetoreflection of light in CoFe 2 O 4 ferrite. The influence of a magnetic field on specular reflection is likely to be indirect: application of a magnetic field results in strong strains and deformations of the crystal lattice, which lead to the change in electron energy structure and hence reflection spectrum of CoFe 2 O 4 crystal - strain-magneto-optics. [ABSTRACT FROM AUTHOR]

For the new ferrimagnetic Heusler alloys Hf 2 CrZ (Z=Al, Ga, In), the structural, electronic, magnetic, elastic properties have been studied by using the first-principles projector augmented wave (PAW) potential within the generalized gradient approximation (GGA+U). The Curie temperatures T c of the Hf 2 CrZ alloys are estimated with mean field approximation (MFA), and the Curie temperatures T c of these three alloys are higher than room temperature. The Hf 2 CrZ (Z=Al, Ga, In) alloys are found to be half-metallic (nearly half-metallic) ferrimagnets within a certain range of lattice constants, the origin of the gap (pseudogap) is well understood. The total magnetic moments of the Hf 2 CrZ alloys are −1 μ B / f .u . for Z=Al, Ga and In, well consistent with Slater-Pauling rule M t = Z t - 18 . Moreover, their elastic constants and the related mechanical properties have also been calculated and discussed. [ABSTRACT FROM AUTHOR]

Development of thermoelectric energy harvesting devices has hit a stumbling block due to the intrinsically linked electrical and thermal conductivities of materials. However, this field can still be improved by employing devices that take advantage of spin-based effects. A temperature gradient can be converted to a spin-polarized current in a ferrimagnetic insulator by the spin Seebeck effect (SSE), and that spin current can be converted to an electrical voltage in a heavy metal by the Inverse spin Hall effect (ISHE). Thus, the thermal energy capture and charge production steps can be separated into two distinct regions of the thermoelectric device, allowing separate tuning of electrical and thermal conductivities. The second step of this process, spin current to electrical voltage conversion, is controlled by the strength and sign of ISHE in the metal, and platinum has become the standard for this purpose. However, here we report a better candidate, β-Tantalum, which shows a spin Seebeck voltage approximately 4 times higher than that of Pt at room temperature. The temperature dependence of spin Seebeck in YIG/β-Ta also closely follows that of YIG/Pt, consistent with magnon spin current theory. The sign of the spin Seebeck voltage in Ta found to be opposite to that of Pt, making the two materials highly complementary for fabricating spintronics-based thermoelectric modules for practical applications. [ABSTRACT FROM AUTHOR]

The phase diagrams and the magnetic properties of a spherical ferrimagnetic nanoparticle, consisting of a ferromagnetic core of atoms A with spin-1/2 ( S A = 1 / 2 ) surrounded by a disordered ferrimagnetic binary alloy shell of two kinds of atoms ( A and B ) with different spins ( S A = 1 / 2 and S B = 3 / 2 ) are studied by using Monte Carlo simulation based on the Metropolis algorithm. Depending on the values of the Hamiltonian parameters, the system presents a number of outstanding phenomena, such as the possibility of one, two or even three compensation point(s). The existence of a compensation temperature is an interesting phenomenon with important technological applications in the field of thermomagnetic recording. [ABSTRACT FROM AUTHOR]

First principles calculations using the self-consistent full-potential linearized augmented plane wave (FPLAPW) method in the framework of density functional theory (DFT) were performed to study the electronic structures and magnetic properties of new full-Heusler compounds Ti 2 VZ (Z=Al, Ga, and In ) . Electronic structure calculations showed that Ti 2 VZ (Z=Al, Ga, and In ) compounds in AlCu 2 Mn-type are conventional ferrimagnets. The Ti 2 VAl, Ti 2 VGa, and Ti 2 VIn compounds in the CuHg 2 Ti-type structure have half-metallic characteristics with a respective majority band gap of 0.52, 0.51, and 0.59 eV at the equilibrium lattice parameter. The origin of half-metallicity in these compounds was also discussed. The total magnetic moments of Ti 2 VZ (Z=Al, Ga, and In ) compounds in the CuHg 2 Ti-type structures were 2 μ B per formula unit which were in agreement with Slater–Pauling rule ( M tot =18 −Z tot ). The Ti 2 VAl, Ti 2 VGa, and Ti 2 VIn compounds in the CuHg 2 Ti-type structure respectively showed half-metallic characteristics at lattice constants ranges of 6.12–7.17 Å, 5.99–7.12 Å, and 6.31–7.06 Å, indicating the lattice distortion did not affect the half-metallic properties of these compounds which makes them interesting materials in the spintronics field. [ABSTRACT FROM AUTHOR]

Abstract: We address the possibility of spiral ferrimagnetic phases in the mean-field phase diagram of the two-dimensional (2D) Hubbard model. For intermediate values of the interaction U ( ) and doping n, a spiral ferrimagnetic phase is the most stable phase in the (n,U) phase diagram. Higher values of U lead to a non-spiral ferrimagnetic phase. If phase separation is allowed and the chemical potential replaces the doping n as the independent variable, the phase diagram displays, in a considerable region, a spiral (for ) and non-spiral (for higher values of U) ferrimagnetic phase with fixed particle density, n=0.5, reflecting the opening of an energy gap in the mean-field quasi-particle bands [Copyright &y& Elsevier]

Abstract: The martensitic transformation in Heusler alloy Mn2PtIn has been investigated by first-principles calculations and experimental studies. Theoretical calculation reveals that, in Mn2PtIn, a transition from cubic structure to tetragonal one is favorable in energy. This has been confirmed by following experimental studies. At room temperature, Mn2PtIn crystallizes in a tetragonal structure of the space group I-4m2. And a transition from tetragonal to cubic Heusler phase occurs at 638K. Mn2PtIn is a ferrimagnet in both austenitic and martensitic phases. Its magnetic properties are mainly determined by the antiparallel aligned Mn spin moments. These findings can greatly enlarge our scope of discovering new FSMAs in Heusler alloys containing 4d and 5d elements. [Copyright &y& Elsevier]

Abstract: The density-functional theory (DFT) within the full potential linearized augmented plane wave (FPLAPW) method is applied to study the two-dimensional achiral soft ferrimagnet [MnII(enH)(H2O)][CrIII(CN)6]·H2O. The phase stability, electronic structure, magnetic and conducting properties are investigated. Our results reveal that the compound has a stable ferrimagnetic ground state in good agreement with the experiment. From the spin density distribution, the spin magnetic moment of the compound is mainly from Cr3+ and Mn2+ ions with small contributions from the oxygen, nitrogen and carbon ions. The calculated electronic band structure predicts the compound to be a half-metal with the spin magnetic moment of 1.000μB per molecule. [Copyright &y& Elsevier]

Abstract: The Monte Carlo simulation technique has been used to study the magnetic behavior of a ferrimagnetic spherical nanoparticle on a simple cubic lattice. The particle is formed by alternate layers of spins and . The interlayer coupling is antiferromagnetic. The influences of the crystal fields, and the exchange couplings, on the critical and compensation behavior of the nanoparticle, are investigated. The results present rich critical behavior, which includes the first- and second-order phase transitions, thus also the tricritical and critical end points. It is also found that the compensation point can appear for appropriate values of the system parameters. [Copyright &y& Elsevier]

In this paper, we have examined in detail the behavior of magnetic properties, hysteresis loops, and compensation phenomenon of a ferrimagnetic mixed spin- (3 ∕ 2 , 2) hexagonal Ising nanowire with alternate layers within the Monte Carlo method based on the Metropolis algorithm. The effect of longitudinal crystal field and exchange coupling constants on the total and the sublattice magnetizations, susceptibilities, specific heat, internal energy, as well as hysteresis loops are investigated for particular parameters. The obtained résults showed different interesting magnetic phenomena, such as seven and triple hysteresis loops at low temperatures, and one or double compensation temperatures under certain parameter values. Our outcomes are also compared with various experimental and theoretical studies. • A hexagonal mixed spin-3/2 and spin-2 Ising ferrimagnetic nanowire with alternate layers, within Monte Carlo simulation techniques. • The effects of the longitudinal crystal fields, the exchange coupling constant, and the temperature on the thermodynamic and magnetic properties and the hysteresis loops were examined in detail. • The seven and triple hysteresis loops at low temperatures, and double compensation temperatures under certain physical parameters. [ABSTRACT FROM AUTHOR]

The fate of exotic spin liquid states with fractionalized excitations at finite temperature (T) is of great interest, since signatures of fractionalization manifest in finite-temperature (T) dynamics in real systems, above the tiny magnetic ordering scales. Here, we study a Jordan–Wigner (JW) fermionized Kitaev spin liquid at finite T employing combined exact diagonalization and Monte Carlo simulation methods. We uncover (i) checkerboard or stripy-ordered flux crystals depending on density of flux, and (i i) establish, surprisingly, that: (a) the finite- T version of the T = 0 transition from a gapless to gapped phases in the Kitaev model is a Mott transition of the fermions, belonging to the two-dimensional Ising universality class. These transitions correspond to a topological transition between a string condensate and a dilute closed string state (b) the Mott "insulator" phase is a precise realization of Laughlin's gossamer (here, p -wave) superconductor (g-SC), and (c) the Kitaev Toric Code phase (TC) is adiabatically connected to the g-SC, and is a fully Gutzwiller-projected fermi sea of JW fermions. These findings establish the finite- T quantum spin liquid phases in the d = 2 to be hidden Fermi liquid(s) of neutral fermions. • Kitaev QSL gapless-phase is described through partially Gutzwiller projected p-wavesuperfluid • Gapless-to-gapped QSL transition analogous to MIT of JW fermions in D = 2 Ising class • Gapped QSL (gossamer spin liquid) to Toric Code phase (JW fermi gas) at large J z [ABSTRACT FROM AUTHOR]

Abstract: The structural, electronic and magnetic properties of the hexagonal nanolaminated layered MAX phases compound Cr2GeC are investigated using the full-potential linearized augmented-plane-waves (FPLAPW) method within the generalized gradient approximation (GGA) and GGA+U calculations. The results indicate Cr2GeC has a sizable moment of 1.667μB revealing the existence of a ferrimagnetic ground state in a MAX phase compound. This surprising new result will lead to the possibility of applying the layered magnetic MAX phase compounds in electronics and spintronics areas. [Copyright &y& Elsevier]

In this study, a quaternary Heusler alloy (QHA) CoYVSn investigated employing density functional theory (DFT) taking into account exchange potential perdew-burke-ernzerhof (PBE) and generalized gradient approximation (GGA). Structural properties revealed that among three different Wyckoff positions, Type I symmetry is found the most stable. Moreover, the ferro-magnetic (FM), non-magnetic (NM) and anti-ferromagnetic (AFM) phases are also considered, and FM phase is found to be the most stable. The structural, elastic, thermal, electronic, and magnetic characteristics are investigated at optimized lattice parameters 6.6151 Å. Electronic properties further investigated using GGA-mBJ functional, results showed that the considered QHA is a SGS. Calculated formation energy (E f) for FM phase suggested that the alloy is stable thermodynamically and experimental realization is possible. Magnetic moment estimated using Slater-Pauling rule; M tot = (N v –18) μ B. The determined elastic properties proved that the alloy fulfills the stability criteria. Debye temperature (θ D) 349 K and melting temperature (T m) 1228 ± 300 K revealed that the alloy is thermally stable. Also, the calculated high Curie temperature (T c) 981 K suggests its suitability for spintronics applications. • Calculations of structural, mechanical, thermal, electronic and magnetic properties. • A spin gapless quaternary Heusler alloy. • High Curie temperature. • Reliable material candidates for applications in ultra-fast and ultra-low-power spintronics devices. [ABSTRACT FROM AUTHOR]

The magnetic properties of Coronene -Like Superlattice (CLS) have been investigated via Monte Carlo study. The system has been described by Hamiltonian contain the (S–S), (σ-σ), (σ-S) spins, external magnetic and the crystal field applied on the two spins S and σ. The several more stable magnetic phases of CLS are obtained under effect of crystal field, exchange interactions and magnetic field. The critical and compensation temperatures of CLS are found for a several exchange interactions between the spins (S–S, σ-S) and crystal fields for a fixed value of exchange interactions between spins σ-σ. Magnetic hysteresis cycles of CLS are obtained for a several temperatures, exchanges interactions (S–S), (σ-σ) and crystal filed D σ. In particular, the results show that the effect of: temperature, exchange coupling, magnetic field and crystallized field, play an important role in the presence of the more saturated magnetic phases and their effect on the magnetic hysteresis cycle. • Magnetic properties of Coronene -Like Superlattice have been investigated via Monte Carlo study. • Several magnetic phases more stable of CLS are obtained. • The critical and compensation temperatures of CLS are found for several exchange interactions and crystal fields applied. • Magnetic hysteresis cycles of CLS for a several temperatures, exchanges interactions (S-S), (s-s) and crystal filed D s. [ABSTRACT FROM AUTHOR]

The crystal, electronic, magnetic and optical properties of the Sr 2 CaOsO 6 double perovskite compounds have been investigated in this work, using density functional theory as implemented in the Full-Potential Linearized Augmented Plane Wave (FP-LAPW) method, employing the Generalized Gradient Approximation (GGA-PBE), GGA + U (Hubbard Coulomb correction) and GGA plus Trans-Blaha-modified Becke–Johnson (TB-mBJ-GGA) as the exchange correlation. According to the structural results, the lattice parameter is in agreed well with the previous experimental data. Spin polarization calculations has shown half-metallic behavior with ferrimagnetic ground state coupling for Ca and Os spins for Sr 2 CaOsO 6 compound. Our calculated electronics results within the TB-mBJ-GGA show that our studied material has direct half-metalic (HM) gaps energy in (Γ v -Γ C) directions with a value equal 2.08 eV and net magnetic moment of 2.000μ B. The most contribution of total magnetic moment is by Osmium atom. For optical properties, it can be concluded that Sr 2 CaOsO 6 material has a high absorption and can be used in future Spintronics and Optoelectronic applications in a large energy range of the light spectrum which extends from visible to ultraviolet. • We consider Sr 2 CaOsO 6 double perovskites compound. • The crystal, electronic, magnetic and optical properties have been investigated. • GGA-PBE, GGA + U and TB-mBJ-GGA approximations have been employed. • Our studied material shows half-metallic behavior with ferrimagnetic ground state. [ABSTRACT FROM AUTHOR]

In this work, we study the magnetic properties of a nanotube core-shell like-structure using Monte Carlo simulations. The system consists of an anti-ferrimagnetic hexagonal core-shell nanotube like-structure with mixed spins σ = 1 in the core and S = 3/2 in the shell. We start by discussing the ground state phase diagrams corresponding to several physical parameters. Then the magnetizations and the susceptibilities have been analyzed. Besides, we explore the thermal magnetization behavior under the effect of the exchange coupling interactions. Furthermore, we investigate the existence of the compensation temperature resulting from the variation of the coupling coefficients. Finally, the variation of the total magnetization and total susceptibility as a function of the exchange coupling interactions and the crystal field has been discussed. • Compensation Behavior of an Anti-ferrimagnetic Core-Shell Nanotube Like-Structure. • Monte Carlo Study has been discussed. • The Monte Carlo simulations technique used to simulate. • The behavior of the Compensation temperature has been established. • A Core-shell nanotube structure has been considered. [ABSTRACT FROM AUTHOR]

In this paper, we study the magnetic properties of a diluted core-shell borophene structure. The system is composed by the mixed spins σ = ±1, 0 (in the core) and S = ±3/2, ±1/2 (in the shell). Indeed, the originality of this work is to introduce the non-magnetic atoms in the shell part of the borophene monolayer system and study their effects on the magnetic properties behavior. Firstly, the ground state phase diagrams for different parameters are reported and discussed. Numerically, we use the Monte Carlo simulations (MCS) to study the effect of the dilution concentration on the magnetizations and susceptibilities of the system. Moreover, the compensation and transition temperatures decrease when increasing the dilution concentration parameter. Furthermore, the effect of the dilution concentration on the total magnetization versus the crystal field is discussed. Finally, the effects of the dilution concentration and the temperature on the hysteresis cycles are investigated. • The magnetic properties of a diluted core-shell borophene structure using Monte Carlo simulations are studied. • The ground state phase diagrams are presented and discussed. • The existence of the compensation and transition temperatures for special physical parameters. • The hysteresis cycles of a core-shell Borophene structure are analyzed. [ABSTRACT FROM AUTHOR]

A core/shell geometric structure is described by ferrimagnetic mixed spin square Blume-Capel Ising nanowire, using MMFM, i.e., molecular mean field method, or rather self-consistent field theory. In this model, antiferromagnetic forms are allowed to spin interactions, i.e. the nearest neighbors. We tested the influence of crystal and external magnetic fields on a ferrimagnetic mixed spin-1 and spin-5/2 square Ising nanowire device, respectively. Spin-1 is located in the middle and in the corners of a rectangular plaquette there are four other spin-5/2. The core-shell ferrimagnetic system shows a point of compensation when exchange couplings are modified for different magnetic field and single-ion anisotropy values. Interesting features are compensation behaviors, where these characteristics found that the mixed spin square nanosystem has two compensation temperatures when D C / | J 1 | = 0 , D S / | J 1 | = − 1.0 , and J 3 = − 0.75 , by application of an external magnetic field, i.e., with h / | J 1 | = − 0.5. • 1. Molecular mean-field method (MMFM) has been used for the study of a ferrimagnetic mixed spin square Blume-Capel Ising nanowire consists of spin-1 core and spin-5/2 outer surface. • Our system has two spin compensation temperatures when , with , and , in the presence of an external magnetic field. • The system experiences a jump which corresponds to the first-order transition to obtain new phases are (−1,0.5), (−1,1.5), for the values of D S / | J 1 | = − 1.0 and D S / | J 1 | = − 0.5 , respectively. [ABSTRACT FROM AUTHOR]

In this work, we study the dielectric properties of a mixed spins (S = 5/2 and σ = 2) and (σ = 5/2 and S = 2) with Blume Capel model in a nanotube structure via Monte Carlo simulations for a several sizes. We start by discussing the ground state phase diagrams corresponding to several physical parameters. Then the polarizations have been analyzed. Besides, we explore the polarization behavior under the effect of the exchange coupling interaction and the crystal anisotropy fields. Furthermore, we investigate the presence of the compensation and critical temperatures resulted from the variation of the coefficient coupling and the crystal anisotropy field. Finally, the variation of the total polarizations as a function of the exchange coupling interaction, the crystal anisotropy field and the temperature have been discussed. • Dielectric properties of a mixed spins with Blume Capel model in a nanotube via Monte Carlo simulations. • Ground state phase diagrams of nanotube for a mixed spins were found. • Polarization behavior under effect of exchange coupling interaction and crystal anisotropy fields has been studied. • Compensation and critical temperatures of nanotube are found. • Hysteresis cycle in ferroelectric material are found in (E, P) plane. [ABSTRACT FROM AUTHOR]

A ferrimagnetic mixed spin square Blume-Capel Ising nanowire system on spin-1 core and spin-3/2 outer shell have been investigated. The general formula for the temperature dependence of the equilibrium magnetization of the system is presented. The ferrimagnetic core-shell nanosystem shows a compensation point when the exchange interactions are changed for different values of the single-ion anisotropies of shell sublattices and core ones, respectively. So, one can examine interesting phenomena are compensation behaviors and the free energy of the nanosystem, where these phenomena found that the mixed-spin square Blume-Capel Ising nanosystem which is being considered has two compensation temperatures in the range of − 0.8 ≤ D B | J 1 | ≤ − 0.4 , respectively. • We have used mean-field approximation(MFA) for the study of a ferrimagnetic mixed spin square Blume-Capel Ising nanowire system consists of spin-1 core and spin-3/2 outer shell. • Particularly, it has been studied the effect of magnetic anisotropies on an existence of compensation temperature. • Our results predict the possibility of two compensation temperatures depending on the negative values of core, shell crystal fieldsand, respectively. [ABSTRACT FROM AUTHOR]

We present theoretical and experimental investigations on the electronic and magnetic properties of the Mn 2+δ Co 0.5-δ V 0.5 Al (δ = 0 ÷ 0.08) and Mn 2+z Co 0.5 V 0.5-z Al (z = −0.14 ÷ 0.08) Heusler alloys. The electronic band structure calculations by the Korringa-Kohn-Rostoker (KKR) Green's function method show the dependence of the total spin moment on the preferential site occupation for different crystal sites and predict compensated ferrimagnetic behavior for the compounds obtained from Mn 2 Co 0.5 V 0.5 Al by slight variation of composition. Experimental investigations by tuning the Mn content in Mn 2 Co 0.5 V 0.5 Al alloys have been performed in order to achieve the fully compensated ferrimagnetic behavior which is of particular importance for spintronics. The thermo-magnetic measurements show different types of ferrimagnetic behavior with the threshold influenced by Mn content: N-type of ferrimagnetic behavior for Mn 2+δ Co 0.5-δ V 0.5 Al, while for the Mn 2+z Co 0.5 V 0.5-z Al Heusler alloys a combined N/P-type of behavior, depending on z, is observed: N-type for Mn excess/P-type for Mn deficiency. The Curie temperatures of the investigated alloys show high sensitivity on the Mn content. The results of our study may give an insight on the influence of the composition on the magnetic properties of the Mn 2 Co 0.5 V 0.5 Al alloys in order to adjust their properties and make them suitable for spintronic applications. • Compensated ferrimagnetism in Mn 2 Co 0.5 V 0.5 Al Heusler alloys by tuning composition. • N/P type of thermomagnetic behavior in Mn 2+z Co 0.5 V 0.5-z Al. • P type of thermomagnetic behavior in Mn 2+δ Co 1-δ V 0.5 Al. • The Curie temperatures are highly compositional sensitive. • Mn 1.96 Co 0.5 V 0.54 Al alloy close to the fully compensated ferrimagnetic behavior. [ABSTRACT FROM AUTHOR]

Polycrystalline samples of Cr substituted gadolinium iron garnets (GdFe 5- x Cr x O 12 ; x = 0 to 0.3) were synthesized in single-phase form via solid-state route. The lattice constant, Fe(a)-Fe(d) bond length and Fe(a)-O-Fe(d) bond angle values are found to decrease with increase in Cr concentration. All samples undergo the interesting magnetic compensation behavior close to the room temperature. In addition to that, they also exhibit ferrimagnetic (FIM) transition with decrease in transition temperature (T c) from 569 K for x = 0 to 518 K for x = 0.3. The observed increase in saturation magnetization at room temperature is explained in terms of preferential occupation of Cr3+ ions at the octahedral site of Fe3+ ions. In addition to magnetic properties, we have also analyzed dielectric and modulus spectra. The room temperature dielectric constant at f = 1 MHz, is found to increase with Cr concentration, i.e. from 15 for x = 0 to 27 for x = 0.3, and it is ascribed to the increase in the charge carriers concentration. Moreover, the modulus data were analyzed using the Bergman function incorporated with the Kohlrausch-Williams-Watts (KWW) function, which suggests that the relaxation dynamics is governed by the short-range movement of charge carriers. • Cr substituted gadolinium iron garnets show magnetic compensation (<303K) and ferrimagnetic transition (>303K). • Dielectric properties have been improved with Cr substitution. • Depressed/asymmetric Modulus spectra indicates the non-ideal Debye type relaxation" [ABSTRACT FROM AUTHOR]