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Spin pumping from canted antiferromagnets is a cutting-edge topic in modern spintronics. The interest for fundamental and applied research that these materials arouse is related to their unusual structure, namely, with a small canting of the magnetic sublattices, which is explained by the presence of the Dzyaloshinskii–Moriya interaction. Through this effect, it becomes possible to experimentally study quasi-ferromagnetic resonance spectra and spin pumping in the range of tens of GHz at room temperature. In this paper, an experimental and theoretical investigation of spin pumping from an antiferromagnet with weak ferromagnetism, α -Fe 2 O 3 , is carried out. The conversion of the precession of the magnetization vector, excited by an alternating magnetic microwave field, into a constant voltage is realized using the inverse spin Hall effect in the hematite/heavy metal structure. Using a constant magnetic field up to 5 kOe, the resonant frequency of such a detector is tunable over a wide range up to 32 GHz with potential sensitivity reaching 10.1 μ V/W. Confirmation of the measurement of the spin current is the change in the sign of V sp when the polarity of the constant magnetic field alters. We believe that these studies will make a major contribution to the understanding of the physics of the spin-pumping effect from antiferromagnets and will also help in the development of devices for quantum technologies and next-generation communication technologies. [ABSTRACT FROM AUTHOR]

Spin pumping from canted antiferromagnets is a cutting-edge topic in modern spintronics. The interest for fundamental and applied research that these materials arouse is related to their unusual structure, namely, with a small canting of the magnetic sublattices, which is explained by the presence of the Dzyaloshinskii–Moriya interaction. Through this effect, it becomes possible to experimentally study quasi-ferromagnetic resonance spectra and spin pumping in the range of tens of GHz at room temperature. In this paper, an experimental and theoretical investigation of spin pumping from an antiferromagnet with weak ferromagnetism, α -Fe 2 O 3 , is carried out. The conversion of the precession of the magnetization vector, excited by an alternating magnetic microwave field, into a constant voltage is realized using the inverse spin Hall effect in the hematite/heavy metal structure. Using a constant magnetic field up to 5 kOe, the resonant frequency of such a detector is tunable over a wide range up to 32 GHz with potential sensitivity reaching 10.1 μ V/W. Confirmation of the measurement of the spin current is the change in the sign of V sp when the polarity of the constant magnetic field alters. We believe that these studies will make a major contribution to the understanding of the physics of the spin-pumping effect from antiferromagnets and will also help in the development of devices for quantum technologies and next-generation communication technologies. [ABSTRACT FROM AUTHOR]

By using first-principles calculations and micromagnetic simulations, we investigate the electronic structure, magnetic properties, and skyrmions in two-dimensional Janus Cr 2 XYTe 6 (X,Y = Si, Ge, Sn, X ≠ Y) monolayers. Our findings reveal that the Cr 2 XYTe 6 monolayers are ferromagnetic semiconductors with a high Curie temperature (T c). The bandgap and T c can be further increased by applying tensile strain. In addition, there is a transition from the ferromagnetic to the antiferromagnetic state at a compressive strain. Both Cr 2 SiSnTe 6 and Cr 2 SiGeTe 6 exhibit a large magnetic anisotropy energy, which are mainly associated with the significant spin–orbit coupling of the nonmagnetic Te atoms rather than that of the magnetic Cr atoms. Interestingly, the Cr 2 SiSnTe 6 monolayer exhibits a significant Dzyaloshinskii–Moriya interaction of 1.12 meV, which facilitates the formation of chiral domain walls and skyrmions. Furthermore, under tensile strain, chiral DWs can be transformed into skyrmions if applying an external magnetic field. These findings suggest that Janus Cr 2 XYTe 6 monolayers hold promise for spintronic nanodevice applications. [ABSTRACT FROM AUTHOR]

Two-dimensional ferromagnetic materials hold great promise to develop energy-efficient magnetoelectric memory devices and next-generation spintronics. However, one of the crucial challenges for these materials is the realization of tunable magnetocrystalline anisotropy (MCA) to balance thermal stability and energy efficiency. Here, we systematically study the adsorption effects of 3d transition metals (3d-TMs) on the electronic structure and magnetic property of the Fe3GeTe2 (FGT) monolayer. The adsorption systems exhibit different ground state configurations depending on the adatoms, while the controlled perpendicular magnetic anisotropy has also been achieved. Notably, the Mn/FGT system can maintain the out-of-plane magnetic orientation with a changing amplitude of MCA energy up to 3.057 erg/cm2 as the external strain varies from −4% to 1%. In contrast, the Fe/FGT structure undergoes spin reorientation from in-plane to out-of-plan magnetization with a distinct modification behavior of MCA. We elucidate that the underlying atomistic mechanism mainly arises from the alteration of Fe-derived 3d-orbital states in response to the strain effect, leading to competitive changes in the different coupling states. These findings can not only provide useful guidance to optimize two-dimensional magnets for fundamental research but also reveal the promising potential of TMs/FGT materials for the development of ultra-low energy spintronic devices. [ABSTRACT FROM AUTHOR]

This paper describes the contributions made by Władysław (Władek) Walukiewicz and his colleagues to the field of ferromagnetic semiconductor (FMS) alloys, such as (Ga,Mn)As. We focus on two key accomplishments. First, this team has predicted the formation of Mn interstitials in these materials, which have a profound effect on ferromagnetism in semiconductors. Additionally, identifying the conditions at which interstitials form has provided grounds for optimizing their ferromagnetic properties. Second, by applying the approach of band anticrossing to ferromagnetic semiconductors, this team has mapped out the properties of an Mn-derived impurity band in these materials. This is of particular importance in the field, because holes, which reside in the Mn-derived impurity band, are the very mechanism responsible for ferromagnetic order in FMSs. We discuss the effect that these accomplishments have on our understanding of FMSs and how they have contributed to progress in this area. We then describe the pathways that these achievements have opened up toward further progress in both basic and applied fronts of ferromagnetism in semiconducting systems; and we present our perspective on where additional work along the lines initiated by Władek Walukiewicz should be extended to further benefit this field. [ABSTRACT FROM AUTHOR]

Magnetic semiconducting materials offer tremendous prospects for spin electronics but is challenging to achieve room-temperature ferromagnetism with unambiguous origin. Herein, a non-stoichiometry strategy is proposed to induce tunable magnetization in MoSe2−x nanoflowers via vacancy-controlled 2H–1T phase transition. The resultant MoSe2−x exhibits robust room-temperature ferromagnetism with significant positive correlation to the content of 1T phase and 2H–1T interfaces. Significant magnetic hysteresis and Curie transition above room temperature have been achieved, confirming the ferromagnetic feature of MoSe2−x. To examine the origin of ferromagnetism, formation energy and spin-polarized calculations have been conducted, indicating that the Se vacancy is beneficial for the formation of the 1T phase and interfacial spin polarization. Localized magnetic moments induced at the 2H–1T interfaces exhibit enhanced magnetism as compared to the net moments from the 1T orbital splitting, giving rise to strong coupling bound magnetic polarons. This work not only advances the understanding on the origin of magnetism in magnetic semiconductors, but also provides an effective route to generate ferromagnetism by defect and/or interface engineering that could be applied to multiferroics, spintronics, and valleytronics. [ABSTRACT FROM AUTHOR]

The search for magnetic topological materials has been at the forefront of condensed matter research for their potential to host exotic states such as axion insulators, magnetic Weyl semimetals, Chern insulators, etc. To date, the MnBi2nTe3n+1 family is the only group of materials showcasing van der Waals-layered structures, intrinsic magnetism and non-trivial band topology without trivial bands at the Fermi level. The interplay between magnetism and band topology in this family has led to the proposal of various topological phenomena, including the quantum anomalous Hall effect, quantum spin Hall effect and quantum magnetoelectric effect. Among these, the quantum anomalous Hall effect has been experimentally observed at record-high temperatures, highlighting the unprecedented potential of this family of materials in fundamental science and technological innovation. In this paper, we provide a comprehensive review of the research progress in this intrinsic magnetic topological insulator family, with a focus on single-crystal growth, characterization of chemical disorder, manipulation of magnetism through chemical substitution and external pressure, and important questions that remain to be conclusively answered.

In this paper, the calcium-doped nickel-zinc nano-ferrites [Ni 0.5 Zn 0.5 Ca x Fe 2-x O 4 ; x = 0.00, 0.10, and 0.30] were prepared using the chemical co-precipitation synthesis route and studied for switching field high-frequency device applications. The structural analysis has been completed by analyzing X-ray diffraction (XRD) patterns. The Rietveld refined XRD patterns confirmed the formation of cubic spinel structure of Ca2+ substituted nickel-zinc ferrites. The detection of metal-oxygen bonds present at A and B lattice sites has been unveiled by Fourier transform infrared (FTIR) spectroscopy. The morphological studies obtained through FESEM (Field emission scanning electron microscopy) analysis showed a reduction in the particle size from 70 nm to 53 nm when the concentration of Ca2+ ions in Ni-Zn ferrites was increased. Energy dispersive spectra (EDS) confirmed the presence of elements present in the prepared composition. The structure of a cubic spinel-shaped unit cell has been verified from three active prominent Raman modes (A 1g , A 2g , and T 2g). Diffuse-reflectance spectroscopy (DRS) exhibits the increment in the bandgap values (from 1.55 eV to 1.63 eV) which helps fabricate highly efficient photovoltaic devices. The ferroelectric measurements yielded a rise in polarization values from 1.461 μC/cm2 to 18.228 μC/cm2 for 10 % Ca2+ ion substitution. The tangent loss values declined from 24 to 3 in Ni-Zn ferrites upon substituting Ca2+ ions. The Vibrating sample Magnetometer (VSM) technique found the increment in the saturation magnetization (M s) values from 34.724 emu/g to 54.662 emu/g on substituting up to 30 % Ca2+ ions in Ni-Zn ferrites. These obtained results support the material in switching field distribution for high-frequency applications. The results exhibited that the prepared samples can be applicable for switching devices, filters, and microwave absorption devices. The results revealed the maximum frequency between 12 and 18 GHz which is useful for Ku band absorption. [ABSTRACT FROM AUTHOR]

Augmentation of optical and magnetic properties of ZnO system via mono- and co-doping is an efficient approach to achieve enhanced ferromagnetism and photocatalytic activity. In this scenario, we made an endeavor to prepare the nanocrystalline ZnO, ZnO:Eu, and ZnO:(Eu, Er) samples through a co-precipitation technique. Structural analysis ruled out the effectual substitution of Eu and Er in the ZnO lattice without disturbing the original structure. Both ZnO:Eu and ZnO:(Eu, Er) NPs exhibited lower optical band gap values than pure ZnO. In M − H studies at room temperature, ferromagnetic behavior was observed in ZnO, ZnO:Eu, and ZnO:(Eu, Er) NPs. Expectedly, ZnO:(Eu, Er) NPs showed highest H 2 evolution than both ZnO and ZnO:Eu NPs beneath solar spectrum. The possible roots behind the extended H 2 production are discussed in detail. Hence, ZnO:(Eu, Er) NPs may find in applications is photocatalysis and spintronics. [ABSTRACT FROM AUTHOR]

The reaction of MnCl2·4H2O with HL ((1-methyl-1H-imidazol-2-yl)methanol) and pdH2 (1, 3 propanediol) in a basic MeCN solution results in the formation of a mixed-valence [Mn20] cationic cluster and two [MnIICl4] counter anions. The metallic skeleton of the cluster describes two geometrically equivalent mixed-valent, linked [MnIII6MnII4] supertetrahedra in which nearest-neighbor metal ions have a different oxidation state. Magnetic susceptibility, magnetization data and heat capacity measurements support evidence of predominant ferromagnetic correlations, leading to a s = 22 spin ground state for the [MnIII6MnII4] supertetrahedra, which are pair-linked by a weak antiferromagnetic coupling. The properties are discussed in the context of the magnetocaloric effect and the potential application of this compound in cryogenic refrigeration. [ABSTRACT FROM AUTHOR]

This study investigates the effects of chromium inclusion on the structural, microstructural, frequency dependent electrical and magnetic properties of SrTiO3 perovskite. The composition of Sr1−xCrxTiO3 (SCT) ceramics with x = 0.00, 0.02, 0.04 is preapred via a high‐temperature solid‐state reaction route. Rietveld refinement of X‐ray diffraction data revealed a cubic structure with space group Pm3¯m$P m \bar{3} m$. All SCT samples have been analyzed for Cr incorporation at the Sr‐site using Raman and Fourier transform infrared spectroscopy. Field‐emission scanning electron microscopy studies probed a gradual increase in grain size due to the uniform distribution of dopants across sample surfaces, as confirmed by energy‐dispersive X‐ray spectroscopy analysis. Cr doping strongly influences the electrical properties of grain and grain boundary resistance. All samples undergo Arrhenius‐type transport via oxygen ion migration and mixed conduction (ionic/electron), whereas relaxation occurs through mixed‐type association (VO··−TiTi4+2+″$V_{\text{O}}^{\cdot \cdot} - \text{Ti}_{\left(\text{Ti}\right)^{4 +}}^{2 +} ^{&aposx; &aposx;}$) and (2CrSr.−TiTi4+2+″$2 \text{Cr}_{\text{Sr}}^{.} - \text{Ti}_{\left(\text{Ti}\right)^{4 +}}^{2 +} ^{&aposx; &aposx;}$). The magnetic nature of Cr‐doped samples confirms room‐temperature ferromagnetism due to carrier‐associated oxygen vacancies and Ruderman‐Kittel‐Kasuya‐Yosida interaction. These findings investigate Cr doping as mixed‐ionic and electronic conductors for intermediate temperature‐solid oxide fuel cells and spintronics‐based semiconductor devices. [ABSTRACT FROM AUTHOR]

Ferromagnetism in the two‐dimensional limit has become an intriguing topic for exploring new physical phenomena and potential applications. To induce ferromagnetism in 2D materials, intercalation has been proposed to be an effective strategy, which could introduce lattice distortion and unpaired spin into the material to modulate the magnetocrystalline anisotropy and magnetic exchange interactions. To strengthen the understanding of the magnetic origin of 2D material, Cu was introduced into a 2D WO3 through chemical intercalation in this work (2D Cu/WO3). In contrast to the diamagnetic nature of Cu and WO3, room‐temperature ferromagnetism was characterized for 2D Cu/WO3. Experimental and theoretical results attribute the ferromagnetism to the bound magnetic polaron in 2D Cu/WO3, which is consist of unpaired spins from W5+/W4+ with localized carriers from oxygen vacancies. Overall, this work provides a novel approach to introduce ferromagnetism into diamagnetic WO3, which could be applied for a wider scope of 2D materials. [ABSTRACT FROM AUTHOR]

Interface engineering is a promising strategy for controlling the Curie temperature (Tc) and perpendicular magnetic anisotropy (PMA) in magnetic 2D van der Waals (2D vdWs)‐based heterostructures. However, establishing high‐quality interface structures in magnetic 2D vdWs/metal stacks, crucial for maximizing interface effects, remains a significant challenge. Here, a Fe5‐xGeTe2/Pt (F5GT/Pt) prototype with a superior interface quality is achieved using a low‐power physical vapor deposition technique. The magnetic properties of the F5GT/Pt heterostructures are strongly influenced by employing the specific physical deposition method. Stable ferromagnetism at 400 K is observed when depositing Pt atoms with relatively high energy, despite the Tc of pristine F5GT being below 300 K. This unexpected high‐temperature ferromagnetism is attributed to the formation of a ferromagnetic alloy at the interface, commonly present in vdWs‐based stacks fabricated through physical deposition but often overlooked. The deposit of Pt atoms with ultralow energy leads to the formation of a unique Fe5‐xGeTe2/Fe3‐xGeTe2 heterojunction at the interface, significantly enhancing the PMA. This work emphasizes the importance of interface structures in vdWs‐based devices, suggesting that controlling the growth process offers an effective approach to construct and engineer vdWs heterostructures, thus improving the performance and introducing new functionalities to spintronic devices. [ABSTRACT FROM AUTHOR]

Herein, the influence of Cr3+ dopant on the structural, morphological, optical, photocatalytic, dielectric and magnetic properties of ZnO was investigated for various applications. Pure ZnO and Cr3+ doped ZnO nanoparticles were synthesised by green mediated approach. The synthesised nanoparticles examined by using XRD, SEM, EDX, FTIR, PL, UV–Vis spectroscopy, dielectric and magnetic analysis. XRD confirmed the wurtizte hexagonal structure of synthesised samples and also revealed that the Cr didn't alter the structure of host ZnO. The FTIR analysis revealed the presence of Cr ions in ZnO structures. Doping of Cr ions improved the optical absorbance of ZnO and the optical band gap showed the blue shift with increasing concentration of Cr. The synthesised Cr doped nanoparticles show the outstanding photocatalytic efficiency under solar irradiation against MG pollutant dye. The dielectric constant (ε) improves and dielectric loss (tan (δ)) reduces at lower frequencies with increasing content of Cr. The AC conductivity for doped nanoparticles showed the increasing trend, especially for 4.5 % Cr doped ZnO nanoparticles. The ferromagnetic behavior at room temperature of Cr doped ZnO nanoparticles confirmed by VSM. The obtained results from all investigations make the Cr doped ZnO samples a potential choice for various applications such as, spin based electronic devices and energy storage devices. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials with inherent magnetism have attracted considerable attention in the fields of spintronics and condensed matter physics. The anomalous Hall effect (AHE) offers a theoretical foundation for understanding the origins of 2D ferromagnetism (2D-FM) and offers a valuable opportunity for applications in topological electronics. Here, we present uniform and large-size 2D Cr7Te8 nanosheets with varying thicknesses grown using the chemical vapor deposition (CVD) method. The 2D Cr7Te8 nanosheets with robust perpendicular magnetic anisotropy, even a few layers deep, exhibit a Curie temperature (TC) ranging from 180 to 270 K according to the varying thickness of Cr7Te8. Moreover, we observed a temperature-induced reversal in the sign of the anomalous Hall resistance, correlating with changes in the intrinsic Berry curvature. Additionally, the topological Hall effect (THE) observed at low temperatures suggests the presence of non-trivial spin chirality. Our findings about topologically non-trivial magnetic spin states in 2D ferromagnets provide a promising opportunity for new designs in magnetic memory spintronics. [ABSTRACT FROM AUTHOR]

Bilayer thin films of GdFeO3/Fe97Si3 have been synthesized by RF–magnetron sputtering at different thicknesses of GdFeO3. A pure phase polycrystalline growth of GdFeO3 and Fe97Si3 has been confirmed by XRD measurements. Stress-induced room-temperature magnetocrystalline anisotropy has been confirmed in all the bilayer thin films. A high magnetic moment has been induced in antiferromagnetic GdFeO3 thin films resulting in the ferromagnetic character of all the samples. The ferromagnetic moment was found to be enhanced with increasing thickness of the GdFeO3 layer. The maximum value of the room- temperature magnetic moment has been observed as Ms ~ 9.3 emu/ml in 170-nm-thick GdFeO3 film. Dielectric measurements confirmed the induced magnetocapacitance due to grain boundary accumulation of charge carriers. Magnetic field control of capacitance and current–voltage measurements of these thin films represents a strong potential for the existence of magnetoelectric coupling in GdFeO3/Fe97Si3 films. A maximum 30% rise in magnetocapacitance and a 95.6% increase in tunneling current in an applied 1-kOe magnetic field was obtained for 170-nm-thick GFO thin film. These thin films possess applications in spintronic devices due to the presence of room- temperature magnetocrystalline anisotropy and magnetic control of the electric properties. [ABSTRACT FROM AUTHOR]

We report the influence of oxygen impurities in generating ferromagnetism in GaN doped with Mn, Fe, and Cr through superexchange involving Mn–O–Mn, Fe–O–Fe, and Cr–N–Cr atomic configurations. Density Functional Theory (DFT) calculations demonstrated that these configurations originate within V Ga - O N complex defects by incorporating Mn2+, Fe2+, and Cr3+ ions into gallium vacancies ( V Ga ) sites promoted by the presence of oxygen as a substitutional impurity ( O N ). These co-doped GaN microstructures were synthesized using the thermal evaporation method. Cathodoluminescence (CL) and photoluminescence (PL) measurements confirmed the presence of V Ga - O N complex defects in all GaN-grown samples. X-ray photoelectron spectroscopy (XPS) measurements confirmed the successful incorporation of Mn2+, Fe2+, and Cr3+ ions in GaN samples. SQUID measurements demonstrated room-temperature ferromagnetism with respective saturation magnetization (Ms) and coercive field (Hc) values of ± 1.5 × 10−5 emu and 4 mT for GaN:O,Mn, ± 4.4 × 10−5 emu and 2.6 mT for GaN:O,Fe, and ± 1.7 × 10−5 emu and 2.6 mT for GaN:O,Cr. [ABSTRACT FROM AUTHOR]

In this article, we have investigated the electronic structure and magnetic properties of Sm2MgMnO6 prepared through auto-combustion method. The first principles of the density-functional theory have been applied to study of the electronic structure. The oxidation states of Mn and Mg are Mn3+/Mn4+ and Mg2+, respectively. The existence of Mn3+ is higher than Mn4+. The magnetic study reveals the sample shows ferromagnetic to paramagnetic transition at around 13.5 K which is followed by an antiferromagnetic ordering at 8.3 K. Antiferromagnetic and ferromagnetic ordering have been identified at 8.3 K and higher temperature, respectively. Sm2MgMnO6 shows a maximum magnetic entropy change of 1.25 J kg-1K-1 and relative cooling power of 86.9 J/kg for a field variation of 70 kOe near 25 K. The values are comparable to many double perovskites reported previously. This study highlights that Sm2MgMnO6 is a potential material for magnetocaloric refrigerant at low temperature. [ABSTRACT FROM AUTHOR]

The effect of Nb doping concentration (0, 1, 2, and 4 at. %) on donor defect‐induced ferromagnetism in ZnO thin films is investigated. The films are deposited on Si(111) substrates utilizing the radio frequency magnetron sputtering. X‐ray diffraction pattern unveils that the films show a pronounced orientation along the (002) direction. The relative intensities of defect‐related bands with that of the ultraviolet band from photoluminescence (PL) spectra show that 2 at. % Nb doping results in a greater number of donor defects (Zni+ and VO+) in the ZnO lattice. The parameters extracted from the electron paramagnetic resonance spectra follow a similar trend. The results from vibrating sample magnetometer measurement indicate that pure ZnO displays diamagnetic nature, whereas Nb‐doped ZnO exhibits a ferromagnetic nature. The saturation magnetization value is found highest for 2 at. % Nb doping, which correlates with the presence of a greater number of donor defects, as supported by the PL and electron paramagnetic resonance results. Images obtained from atomic force microscopy show that the surface roughness of the ZnO thin film reduces upon Nb doping. X‐ray photoelectron spectroscopy validates that Nb is doped in 2 at. % Nb‐doped ZnO thin film with Nb oxidation state of +5. [ABSTRACT FROM AUTHOR]

It is well known that the properties of a crystal evolve as it increases in size from a single atomic plane to that of the bulk. Such size‐dependent transitions can stem from many different origins and depend on minute changes to crystal bonding and composition. A model example is that of LaCoO3, which is non‐magnetic in the bulk but can display ferromagnetism at the nanoscale. Here, the evolution of structure‐property relationships is studied in the LaCoO3−δ/SrTiO3 (001) system as the thickness of LaCoO3−δ is increased from a single plane to 10 unit cells. In situ synchrotron X‐ray studies are performed during and post‐deposition to probe changes in the interactions between structure, stoichiometry, and magnetic behavior. Structural quantification indicates that the oxygen octahedral rotation pattern evolves with thickness, due to inherent differences in crystal symmetry between the film and substrate. The change in rotation modifies the required energy barrier for the spin state transition via the Co–O bond length and Co–O–Co bond angle, affecting the appearance of ferromagnetism. Our results highlight the contributions of high spin Co2+ and/or high spin Co3+ to respective weak and robust ferromagnetism and the evolution of properties with size in ultrathin LaCoO3−δ heterostructures. [ABSTRACT FROM AUTHOR]

Cubic, perovskite‐structure ABO3‐ and A1−xA'xBO3‐type oxides have been investigated extensively while their hexagonal structure versions have not, even though they are multiferroic and can form heterostructures with hexagonal 2D materials. In particular, multiferroic 2D epilayers may lead to strong magnetoelectric coupling. Hexagonal RFeO3 ferrites, where R is a rare‐earth element (Lu, Yb, etc.), are excellent candidates, but their ferromagnetism is weak. In this work, density‐functional‐theory (DFT) calculations are employed and first show that heavy electron doping of hexagonal LuFeO3 (h‐LFO), namely Lu1−xHfxFeO3 (h‐LHFO), leads to spin‐disproportionation of the Fe sublattices and, especially for x = 1/2 and 2/3, to robust, room‐temperature, out‐of‐plane, collinear ferrimagnetism that is stabilized by a Jahn–Teller metal‐to‐insulator transition. h‐LHFO/h‐2D heterostructures are then shown, where h‐2D is the FE/FM monolayer MnSTe, to stabilize skyrmions without an external magnetic field and their chirality is controlled by an external electric field through the h‐LHFO polarization, opening up a new realm for magnetoelectric applications. [ABSTRACT FROM AUTHOR]

We present a systematic investigation of the detailed structural, optical and magnetic properties of ZnO thin films deposited by pulsed laser deposition as a function of varying Al doping from 0% to 5%. The observed features can be associated with strain introduced into the ZnO lattice by the incorporation of Al. Enhanced optical transmittance values close to 95% were achieved in Al-doped ZnO epitaxial films deposited on sapphire substrates. In addition, these films exhibit robust ferromagnetic properties at room temperature with saturation magnetization that varies from 143 to 63 emu/cm3 for Al dopant concentrations from 0% to 5%. It is demonstrated that the saturation magnetization is related to the strain introduced into the lattice with increased Al doping. [ABSTRACT FROM AUTHOR]

We calculate the conductance of a junction between a disordered superconductor and a very strong half-metallic ferromagnet admitting electrons with only one spin projection. A usual mechanism of Andreev reflection is strongly suppressed in this case since Cooper pairs are composed of electrons with opposite spins. However, this obstacle can be overcome if we take into account spin-orbit scattering inside the superconductor. Spin-orbit scattering induces a fluctuational (zero on average) spin-triplet component of the superconducting condensate, which is enough to establish Andreev transport into a strong ferromagnet. This remarkably simple mechanism is quite versatile and can explain long-range triplet proximity effect in a number of experimental setups. One particular application of the suggested effect is to measure the spin-orbit scattering time τ SO in disordered superconducting materials. The value of Andreev conductance strongly depends on the parameter Δ τ SO and can be noticeable even in very disordered but relatively light metals like granular aluminum. [ABSTRACT FROM AUTHOR]

The study of exchange bias in various types of systems received great attention due to widespread applications in numerous magnetoelectronic devices and, in particular, understanding and controlling exchange bias in single layer films becomes crucial in advancing the spintronics field. With this connection, we here present a study on the origin of the exchange bias in the Fe3O4 (t nm) films with a polycrystalline structure fabricated via magnetron reactive sputtering directly onto a Si(100) substrate at ambient conditions and its correlation with thickness of the films and cooling fields. Structural and morphological studies reveal single phase polycrystalline Fe3O4 films and the average roughness increases with increasing thickness of the films. Magnetic properties show typical ferromagnetic behavior in Fe3O4 film, but interestingly, a considerable exchange bias (EB) of 550 Oe is noticed in 30 nm thick Fe3O4 film at 10 K when subjected to field cool. In addition, Fe3O4 (30 nm) film exhibits a spontaneous exchange bias without any external applied field. These observations can be understood from the magnetic exchange coupling at the interfaces between the ferromagnetic Fe3O4 and antiferromagnetic FeO, and the existence of a FeO can be validated from the magnetic anomalies in thermomagnetization data. Furthermore, the magnetic anomalies fade out at higher film thicknesses due to reduced (increased) volume of FeO (Fe3O4), causing suppression in the EB effect. The variation of EB with cooling field and film thickness demonstrates the tunability of EB in single layer Fe3O4 film and its suitability for possible applications in spintronics. [ABSTRACT FROM AUTHOR]

Conventional solid-state reaction method has been cautiously employed to prepare the Ba0.75Sr0.25Ti1−xMnxO3 ceramic where Sr was firmly doped at the Ba site and Mn was doped with different densities at the Ti site. Since the performance of materials varies with frequency, electric field, and temperature, we have elucidated the various features of the synthesized samples for the sake of scientific benefit in the fields of microelectronics, telecommunications, and spintronics. Structural and morphological features of the ready samples were examined by X-ray diffraction and scanning electron microscopy (SEM). The crystal's tetragonal behavior was verified by XRD analysis, and with the increment of Mn content, the volume of the unit cell is little changed. It is clear from the SEM images that the grain size of the prepared samples increases with Mn doping. The dielectric properties of Ba0.75Sr0.25Ti1−xMnxO3 were measured by dielectric constant and AC conductivity in a wide range of frequency from 1 kHz to 10 MHz. This result also explores that the dielectric constant rises with the concentration of Mn, most significantly for the 20% Mn substitution with Ti. We also found from the experimental result that the dielectric constant is high in the frequency range of 1–10 kHz. The magnetic permeability of the prepared sample increased with 10% and 20% of Mn replacement. Ferromagnetic features with a weak coercive field and the increased ferromagnetic order with rising Mn concentrations of the prepared samples were confirmed by VSM data analysis. The developed multiferroic materials can be employed in future spintronic devices like spin transistors, sensors, spin diodes, and memory devices. [ABSTRACT FROM AUTHOR]

Analogies from other systems provide theoretical insights, modeling tools, and empirical methods for studying belief dynamics. Frequently used analogies include epidemics, ferromagnetism, forces, evolution, thresholds, weighted additive models, and Bayesian learning. Analogies that inspire models of belief dynamics can provide conceptual mileage by highlighting valuable insights and similarities between the base and target phenomena. However, they can also introduce conceptual baggage when certain aspects of the analogy are inappropriately extended to the target domain, leading to incorrect conclusions. Cognitive scientists could advance the study of belief dynamics by considering analogies with other systems, providing translations of analogical concepts into relevant cognitive and social processes, and comparing implications of models based on different analogies with empirical data. Belief dynamics has an important role in shaping our responses to natural and societal phenomena, ranging from climate change and pandemics to immigration and conflicts. Researchers often base their models of belief dynamics on analogies to other systems and processes, such as epidemics or ferromagnetism. Similar to other analogies, analogies for belief dynamics can help scientists notice and study properties of belief systems that they would not have noticed otherwise (conceptual mileage). However, forgetting the origins of an analogy may lead to some less appropriate inferences about belief dynamics (conceptual baggage). Here, we review various analogies for modeling belief dynamics, discuss their mileage and baggage, and offer recommendations for using analogies in model development. [ABSTRACT FROM AUTHOR]

This article reports the in-situ growth of spinel CoCr 2 O 4 nanocrystals (NC) in tellurite glass through tailoring the Co content by melt-quenching method. The microstructure, optical, and magnetic properties of NC/ glass systems were systematically studied using various techniques. Well-defined 30 nm crystallization of CoCr 2 O 4 (space group of Fd3m) homogeneously distributed in the glassy matrix and the concurrent formation of cubic BiCoO 3 (space group of P4mm) when the Co content exceeds 3%. The coexistence of multivalence and coordination states of Co and Cr significantly modified the glass structure with conversion of TeO 4 →TeO 3 , BO 4 →BO 3 , and CoO 4 →CoO 6 units. Exceptional performance of the glass containing 5% Co-tuned CoCr 2 O 4 was obtained, showcasing the decrease of E g (2.09 eV), strong ferro-magnetization of 7.04 emu/g, large α 3 (4.88×10−10 m/W) and good optical limiting property (threshhold of 1.31×1012 W/m2). Furthermore, the same glass showed excellent red emission between 650 and 800 nm under the excitation of 460 nm, with an increased lifetime (2.648 ms) and good stability of 90.7% within 25–300 °C. The emission mechanism was discussed. EPR analysis confirmed the active role and spin-states of magnetic Cr and Co ions, contributing synergistically to the improved optical and magnetic properties of the glasses. [ABSTRACT FROM AUTHOR]

Here we report the structural, optical and magnetic properties of La0.4Pr0.25NaxSr0.35−xMnO3 (x = 0, 0.05, and 0.1) synthesized using ball milling method. After milling, the precursors are calcinated at 1,200 °C for 12 h. The phase purity, crystal structure, lattice parameter, and crystallite size of the samples were determined using X‐ray diffraction (XRD). The peaks from XRD provide the perovskite hexagonal structure with an R 3 ‾ c space group. Surface morphology shows the recreation of spherical structure to nanoflakes/layered structures. The ultraviolet-visible diffused reflectance spectroscopy (UV–vis DRS) study indicates that the decrease in the band gap is observed with the increase of Na content. The intensity of the luminescence peak decreases progressively with the increase of Na doping. The room temperature (RT) magnetization of the samples reveals weak ferromagnetism and shows a novel vertical shift in magnetization at room temperature. [ABSTRACT FROM AUTHOR]

In the pursuit of high‐spin building blocks for the formation of covalently bonded 1D or 2D materials with controlled magnetic interactions, π ${\pi }$ ‐electron magnetism offers an ideal framework to engineer ferromagnetic interactions between nanographenes. As a first step in this direction, we explore the spin properties of ferromagnetically coupled triangulenes—triangular nanographenes with spin S=1 ${S = 1}$ . By combining in‐solution synthesis of rationally designed molecular precursors with on‐surface synthesis, we successfully achieve covalently bonded S=2 ${S = 2}$ triangulene dimers and S=3 ${S = 3}$ trimers on Au(111). Starting with the triangulene dimer, we meticulously characterize its low‐energy magnetic excitations using inelastic electron tunneling spectroscopy (IETS). IETS reveals conductance steps corresponding to a quintet‐to‐triplet excitation, and a zero‐bias peak resulting from higher‐order spin‐spin scattering of the five‐fold degenerate ferromagnetic ground state. The Heisenberg model captures the key parameters of inter‐triangulene ferromagnetic exchange, and its successful extension to the larger S=3 ${S = 3}$ system validates the model's accuracy. We anticipate that incorporating ferromagnetically coupled building blocks into the repertoire of magnetic nanographenes will unlock new possibilities for designing carbon nanomaterials with complex magnetic ground states. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) van der Waals (vdW) magnets are crucial for ultra-compact spintronics. However, so far, no vdW crystal has exhibited tunable above-room-temperature intrinsic ferromagnetism in the 2D ultrathin regime. Here, we report the tunable above-room-temperature intrinsic ferromagnetism in ultrathin vdW crystal Fe3+xGaTe2 (x = 0 and 0.3). By increasing the Fe content, the Curie temperature (TC) and room-temperature saturation magnetization of bulk Fe3+xGaTe2 crystals are enhanced from 354 to 376 K and 43.9 to 50.4 emu·g−1, respectively. Remarkably, the robust anomalous Hall effect in 3-nm Fe3.3GaTe2 indicates a record-high TC of 340 K and a large room-temperature perpendicular magnetic anisotropy energy of 6.6 × 105 J m−3, superior to other ultrathin vdW ferromagnets. First-principles calculations reveal the asymmetric density of states and an additional large spin exchange interaction in ultrathin Fe3+xGaTe2 responsible for robust intrinsic ferromagnetism and higher TC. This work opens a window for above-room-temperature ultrathin 2D magnets in vdW-integrated spintronics. [ABSTRACT FROM AUTHOR]

Recent developments have introduced a groundbreaking form of collinear magnetism known as “altermagnetism”. This emerging magnetic phase is characterized by robust time‐reversal symmetry breaking, antiparallel magnetic order, and alternating spin‐splitting band structures, yet it exhibits vanishing net magnetization constrained by symmetry. Altermagnetism uniquely integrates traits previously considered mutually exclusive to conventional collinear ferromagnetism and antiferromagnetism, thereby facilitating phenomena and functionalities previously not achievable within these traditional categories of magnetism. Initially proposed theoretically, the existence of the altermagnetic phase has since been corroborated by a range of experimental studies, which have confirmed its unique properties and potential for applications. This review explores the rapidly expanding research on altermagnets, emphasizing the novel physical phenomena they manifest, methodologies for inducing altermagnetism, and promising altermagnetic materials. The goal of this review is to furnish readers with a comprehensive overview of altermagnetism and to inspire further innovative studies on altermagnetic materials which can potentially revolutionize applications in technology and materials science. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) van der Waals (vdW) magnets are crucial for ultra-compact spintronics. However, so far, no vdW crystal has exhibited tunable above-room-temperature intrinsic ferromagnetism in the 2D ultrathin regime. Here, we report the tunable above-room-temperature intrinsic ferromagnetism in ultrathin vdW crystal Fe3+xGaTe2 (x = 0 and 0.3). By increasing the Fe content, the Curie temperature (TC) and room-temperature saturation magnetization of bulk Fe3+xGaTe2 crystals are enhanced from 354 to 376 K and 43.9 to 50.4 emu·g−1, respectively. Remarkably, the robust anomalous Hall effect in 3-nm Fe3.3GaTe2 indicates a record-high TC of 340 K and a large room-temperature perpendicular magnetic anisotropy energy of 6.6 × 105 J m−3, superior to other ultrathin vdW ferromagnets. First-principles calculations reveal the asymmetric density of states and an additional large spin exchange interaction in ultrathin Fe3+xGaTe2 responsible for robust intrinsic ferromagnetism and higher TC. This work opens a window for above-room-temperature ultrathin 2D magnets in vdW-integrated spintronics. [ABSTRACT FROM AUTHOR]

Topological semimetals, possessing topologically non-trivial band structures, serve as excellent platforms for realizing topological superconductivity through hard point-contact experiments. In this study, we successfully induce superconductivity in the three-dimensional Dirac semimetal, cubic PtBi2, using ferromagnetic and paramagnetic tips in hard point contact experiments. The induced superconductivity is proven to be insensitive to ferromagnetism and exhibits unconventional features in the point-contact spectra. The highest superconducting transition temperature ( T c ) reaches approximately 5.1 K, and the T c values are proven to have a positive correlation with the coupling between the tip and the sample. Furthermore, we extend our point-contact experiments to trigonal PtBi2, a material possessing a type-I Weyl semimetal band structure and triply degenerate points proximate to the Fermi level. Utilizing both ferromagnetic Ni tips and paramagnetic Ag tips, we successfully enhance superconductivity with a T c of up to 3.0 K in this material. The findings from point-contact measurements reveal that the enhanced superconductivity is compatible with ferromagnetism and the magnetism of the tip can affect the symmetry of the enhanced superconducting state. Given that the lattice structure remains stable under pressure up to 51.2 GPa for cubic PtBi2 and 12.9 GPa for trigonal PtBi2, the emergent superconducting states observed in these two PtBi2 materials could inherit their topological nontrivial nature and be promising candidates for topological superconductor. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) Janus materials are a fascinating class of materials resulting from their unique electronic and magnetic properties induced by mirror symmetry breaking. However, 2D Janus materials with intrinsic magnetism remain rather rare, casting a mysterious veil over magnetism. In this work, the electronic and magnetic properties of Janus Mn2GeX (X = As, Sb) monolayers using the first‐principles calculations are investigated. The results demonstrate that these Janus materials exhibit excellent mechanical and dynamic stability, indicating their potential for future applications in nanoscale spintronic devices. Interestingly, the Janus Mn2GeAs$\left(\text{Mn}\right)_{2} \text{GeAs}$ and Mn2GeSb$\left(\text{Mn}\right)_{2} \text{GeSb}$ monolayers possess exciting half‐metallic character with wide half‐metallic gaps of 0.29 and 0.18 eV, and spin gaps of 1.68 and 1.62 eV, respectively. Their calculated ground state exhibits a strong preference for ferromagnetic ordering, with a Curie temperature (Tc$T_{c}$) of 630 and 590 K, respectively. Additionally, the ferromagnetism of Janus Mn2GeX (X = As, Sb) monolayers is robust against biaxial strain ranging from −6% to 6%. Under 6% tensile strain, the calculated Tc$T_{c}$ of the Mn2GeSb$\left(\text{Mn}\right)_{2} \text{GeSb}$ monolayer is 639 K, which represents a 9% increase compared to the Tc$T_{c}$ observed in the unstrained condition. All these intriguing electronic and magnetic properties make the Janus Mn2GeX (X = As, Sb) monolayers an appealing candidate for applications in nanoscale spintronic devices. [ABSTRACT FROM AUTHOR]

For temperatures below and beyond the Curie temperature, the stochastic Landau-Lifshitz-Bloch equation describes the evolution of spins in ferromagnetic materials. In this work, we consider the stochastic Landau-Lifshitz-Bloch equation driven by a real valued Wiener process and show Wong-Zakai type approximations for the same. We consider non-zero contribution from the helicity term in the energy. First, using a Doss-Sussmann type transform, we convert the stochastic partial differential equation into a deterministic equation with random coefficients. We then show that the solution of the transformed equation depends continuously on the driving Wiener process. We then use this result, along with the properties of the said transform to show that the solution of the originally considered equation depends continuously on the driving Wiener process. [ABSTRACT FROM AUTHOR]

We study the effect of hole doping on the Kitaev spin liquid (KSL) and find that for ferromagnetic (FM) Kitaev exchange K the system is very susceptible to the formation of a FM spin polarization. Through density matrix renormalization group simulations on finite systems, we uncover that the introduction of a single hole, corresponding to ≈1% hole doping for the system size we consider, with a hopping strength of just t ~ 0.28K is enough to disrupt fractionalization and polarize the spins in the [001] direction due to an order-by-disorder mechanism. Taking into account a material relevant FM anisotropic exchange Γ drives the polarization towards the [111] direction via a transition into a topological FM state with chiral magnon excitations. We develop a parton mean-field theory incorporating fermionic holons and bosonic magnons, which accounts for the doping induced FM phases and topological magnon excitations. We discuss experimental implications for Kitaev candidate materials. [ABSTRACT FROM AUTHOR]

Here, we show that the ferro(para)magnetic and non-collinear antiferromagnetic interfaces contribute to oscillating signals observed in the magnetoresistance. We associate the effect with the fact that the spins on the surface of IrMn 3 produce instability in the surface magnetoresistance of the material, which is sensitive to the magnetic field. We carried out experiments using bilayers of IrMn 3 under permalloy (Py) and IrMn 3 under platinum (Pt). The oscillations were intensely evident at the Py/IrMn 3 interface and less explicit at the Pt/IrMn 3 interface. We carried out the experiments using pulsed current, with a square pulse width of 1 μ s and amplitudes of I AC = 20 μ A to 20 mA. The oscillating signals are proportional to the crystallographic direction of the material, the ferromagnetism of the material adjacent to IrMn 3 , and sensitive to the amplitude of the pulsed current. We believe that observation is a way of transmitting encoded information through magnetoresistance. [ABSTRACT FROM AUTHOR]

Computational methods of DFT were utilized to predict the lattices constants, electronic structures, half-metallic character and ferromagnetic properties of Ga1 − xCrxSb compounds at compositions x = 0.25, 0.5, and 0.75. The direct gap of GaSb found with potential TB-mBJ agrees with those calculated with TB-mBJ and HSE06 potentials. Investigations of magnetic and electronic properties using TB-mBJ show that the substituting compounds exhibit integer values of total moments, and they reveal better half-metallic ferromagnetic gaps of 1.269, 1.16, and 1.262 eV respectively for Ga0.75Cr0.25Sb, Ga0.5Cr0.5Sb, and Ga0.25Cr0.75Sb, with spin polarizations of 100%. Therefore, Ga0.75Cr0.25Sb, Ga0.5Cr0.5Sb, and Ga0.25Cr0.75Sb are suitable magnetic compounds for spintronics applications. [ABSTRACT FROM AUTHOR]

Thin films of FePtCo ternary alloy with 100 nm thickness have been deposited on an Si substrate using a DC magnetron sputtering system by co-sputtering of Co metal target and Fe40Pt60 alloy target in three different conditions, i.e. as-deposited at room temperature, annealed at 400 °C ${}_{}^ \circ C$ ∘ C , and deposited on the seed- layer. The effects of target sputtering power, leading to different compositions and various deposition conditions on surface roughness of films and magnetic properties, were studied. The average surface roughness of the as-deposited films decreases with the increase in the sputtering power of the Co target. For the annealed and seed-layered films, an increase in Co sputtering power resulted in an increased in roughness. Moreover, the annealed films possess smallerlower roughness due to an increase in the surface mobility. On the other hand, the Cu seed- layer decreases the roughness by preventing the diffusion of the film into the substrate. The room -temperature M-H measurement shows that the films exhibit soft ferromagnetism with coercivity in the order of ${10^3}$ 10 3 A/m and large saturation magnetizationmagnetisation of the order ${10^6}$ 10 6 A/m. The saturation magnetizationmagnetisation decreases with the increase in the sputtering power and is not influenced by the film surface roughness. On the other hand, riseincrease in surface roughness leads to decrease in coercivity of the films. HIGHLIGHTS: Thin films of FePtCo ternary alloy have been deposited by co-sputtering of Co metal target and Fe40Pt60 alloy target. The effects of surface roughness of films on magnetic properties were studied. The room-temperature M-H measurement shows that the films exhibit soft ferromagnetism. The saturation magnetisation decreases with sputtering power and is not influenced by the film surface roughness. On the other hand, increase in surface roughness leads to decrease in coercivity of the films. [ABSTRACT FROM AUTHOR]

A facile method has been employed to synthesize pristine and Cr-doped SnS2 (Cr: SnS2) nanoplates (Sn1-xCrxS2, here x = 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0) and Cr: SnS2 nanoplates (NPs) were successfully synthesized via hydrothermal method. The nanoplates' structure was hexagonal, with a preference for orientation along the (001) plane; there was no evidence of additional undesirable phases. FTIR and EDX were used to observe the existence of functional groups in the samples where Sn-S bonds were present in each of the produced pristine and Cr: SnS2 nanoplates. XPS measurements demonstrated the existence of Sn, S, and Cr. FESEM revealed that the morphological properties of the nanoplates included several hexagonal grains. Magnetic characterizations showed that with increasing doping concentration of Cr, SnS2 nanoplates become superparamagnetic from ferromagnetic. The band gap values for the pristine and Cr: SnS2 nanoplates calculated from the absorbance spectra decreased from 2.53 to 2.08 eV with an increase in doping concentration. The photoluminescence spectra of the pristine SnS2 and Cr: SnS2 nanoplates exhibit two strong emission peaks at around 562 and 666 nm for an excitation wavelength of 420 nm. The Cr: SnS2 nanoplates have demonstrated the resistive behavior of the sample. The Cr: SnS2 nanoplates have shown good photocatalytic activity towards the decolorization of rhodamine B under visible irradiation.Article highlights: Hydrothermally synthesized pristine SnS2 and Cr: SnS2 nanoplates exhibit hexagonal crystal structures and the hexagonal shape of layered nanoplates is apparent in both cases. The ferromagnetic order is introduced by Cr doping in SnS2 which increases the formation of dilute magnetic semiconductors that can therefore be used in spintronic devices. The Sn0.6Cr0.4S2 photocatalyst shows the highest photocatalytic activity and a degradation efficiency of 71%, which is 3.4 times higher than the pure SnS2 catalyst. [ABSTRACT FROM AUTHOR]

During the last two decades, researchers have been making efforts to find the most suitable metal oxides to be utilized for spintronics applications, magneto-optical devices, quantum dots, etc. Thus current research has examined the microstructural, optical, dielectric, and magnetic behavior of co-doped (Cr, Fe) tin oxide (Sn1−2xCrxFexO2−δ) nanoparticles. The Cr and Fe-doped (Sn1−xCrxO2−δ), (Sn1−xFexO2−δ) and co-doped (Cr, Fe) tin oxide (Sn1−2xCrxFexO2−δ) for x = 0.1 have been synthesized by solid-state reaction method from the tin oxide, chromium oxide, and ferric oxide prepared by co-precipitation method. Powder x-ray diffraction reveals the formation of pure rutile type tetragonal phase of samples and average crystalline size was found to be in the range of 45–54 nm. The electronic state of elements Sn, Cr, and Fe was observed to be 4+, 6+, and 3+, respectively, from x-ray photoelectron spectroscopy. The shape and size of the particles were observed to be cubic and in the range of 52–70 nm by scanning electron microscope. On the other hand, transmission electron microscopic reveals the grain size of 25–36 nm. The optical band gap determined from UV–visible absorption spectroscopy was found to be widened by doping. The maximum dielectric loss (5.3) was observed for pristine SnO2 and low loss (0.78) for co-doped (Cr, Fe) tin oxides from P–E measurement. The vibrating sample magnetometer studies show the transition from diamagnetism to ferromagnetism after co-doping. We found improvement in ferromagnetism and ferroelectricity due to co-doping, therefore the sample is suitable for high-frequency optoelectronic applications. [ABSTRACT FROM AUTHOR]

Using state-of-the-art first-principles electronic-band-structure calculations alongside density functional theory, we investigated the structural, elastic, electronic, and magnetic properties of LiMnZ2 (Z = Se, Te) compounds with a trigonal structure. Initially, we determined the equilibrium lattice structure and atomic positions, which aligned well with experimental values. Ferromagnetism was shown to be more favorable than the non-magnetic state. The elastic constants, cohesive energies, and formation energies indicated that the studied compounds were mechanically stable in the experimentally determined trigonal lattice. The analysis of spin-polarized band structures and density of states revealed that both LiMnZ2 compounds exhibited perfect half-metallic characters. The total spin magnetic moment per formula unit adhered to the Slater–Pauling rule, being exactly 4 μΒ, mainly concentrated at the Mn atoms due to the strong spin polarization of the Mn d orbitals. We anticipate that our results will prompt further experimental and computational studies for the application of these layered materials in practical devices. [ABSTRACT FROM AUTHOR]

Here, by using angle-resolved photoemission spectroscopy, we showed that Bi2−xCrxSe3 single crystals have a distinctly well-defined band structure with a large bulk band gap and undistorted topological surface states. These spectral features are unlike their thin film forms in which a large nonmagnetic gap with a distorted band structure was reported. We further provide laser-based high resolution photoemission data which reveal a Dirac point gap even in the pristine sample. The gap becomes more pronounced with Cr doping into the bulk of Bi2Se3. These observations show that the Dirac point can be modified by the magnetic impurities as well as the light source. [ABSTRACT FROM AUTHOR]

The magnetoelectric (ME) response of laminated composites consisting of BaFe12O19 and Pb(Zr,Ti)O3 ceramics is systematically investigated. A butterfly-shaped curve of a magnetoelectric coefficient emerges in both three-layer and multilayer composites. We show that the appearance of a 7 ppm residual strain in the BaFe12O19 layer after magnetization is the main reason for this special curve. We also observe the self-biasing effect of the composites and a maximum ME response from 0.6 to 5 mV/(Oe cm) in laminated composites with magnetic and ferroelectric layers of different thicknesses that can be measured at a zero-bias magnetic field. The repeatable and stable maximum and minimum values of the magnetoelectric coefficient can be obtained under periodically applied biasing magnetic fields, which is important for a practical device application. An electric-field control of ferromagnetism, evidenced by a 17%–19% enhancement in the magnetization of the BaFe12O19 layer after Pb(Zr,Ti)O3 is polarized, is observed in the composites, implying potential applications in memory devices for the composites. Our work indicates that both magnetic field-controlled polarization and electric-field-controlled magnetization exist in BaFe12O19/Pb(Zr,Ti)O3 laminated composites. [ABSTRACT FROM AUTHOR]

We synthesized La2NiO4 nanostructures using the cationic surfactant-based reverse micellar route and reported on the effect of the size and shape of the La2NiO4 nanostructures on their magnetic and photoelectrochemical properties. We satisfactorily refined the powder X-ray diffraction data in the tetragonal space group, I4/mmm. Magnetic susceptibility measurements were performed on all samples within the range of 5–300 K. The Curie–Weiss law determines the magnetic susceptibility of bulk La2NiO4, and a negative value for the Weiss temperature indicates antiferromagnetic exchange. The field-dependent magnetization curves of bulk La2NiO4 suggest a canted antiferromagnetic behaviour. The Mott–Schottky plot demonstrates that La2NiO4 is a p-type semiconducting material with holes as the primary charge carriers. Chronoamperometric measurements for these nanomaterials demonstrate excellent photostability of photocurrent. [ABSTRACT FROM AUTHOR]

The exploration of magnetism in two-dimensional layered materials has attracted extensive research interest. For the monoclinic phase CrI3 with interlayer antiferromagnetism, finding a static and robust way of realizing the intrinsic interlayer ferromagnetic coupling is desirable. In this work, we study the electronic structure and magnetic properties of the nonmagnetic element (e.g., O, S, Se, N, P, As, and C) doped bi-and triple-layer CrI3 systems via first-principles calculations. Our results demonstrate that O, P, S, As, and Se doped CrI3 bilayer can realize interlayer ferromagnetism. Further analysis shows that the interlayer ferromagnetic coupling in the doped few-layer CrI3 is closely related to the formation of localized spinpolarized state around the doped elements. Further study presents that, for As-doped tri-layer CrI3, it can realize interlayer ferromagnetic coupling. This work proves that nonmagnetic element doping can realize the interlayer ferromagnetically-coupled few-layer CrI3 while maintaining its semiconducting characteristics without introducing additional carriers. [ABSTRACT FROM AUTHOR]

In spintronics, transverse anomalous transport properties have emerged as a highly promising avenue surpassing the conventional longitudinal transport behaviors. Here, we explore the transverse transport properties of monolayer and bilayer Fe3−xCoxGaTe2 (x = 0.083, 0.167, 0.250, and 0.330) systems. All the systems exhibit ferromagnetic ground states with metallic features and also have perpendicular magnetic anisotropy. Besides, the magnetic anisotropy is substantially enhanced with increasing Co-doping concentration. However, unlike magnetic anisotropy, the Curie temperature is suppressed by increasing the Co-doping concentration. For instance, the monolayer and bilayer Fe2.917Co0.083GaTe2 hold a Curie temperature of 253 K and 269 K, which decreases to 163 K and 173 K in monolayer and bilayer Fe2.67Co0.33GaTe2 systems, respectively. We find a giant anomalous Nernst conductivity (ANC) of 6.03 A/(K·m) in the monolayer Fe2.917Co0.083GaTe2 at −30 meV, and this is further enhanced to 11.30 A/(K·m) in the bilayer Fe2.917Co0.083GaTe2 at −20 meV. Moreover, the bilayer Fe2.917Co0.083GaTe2 structure has a large anomalous thermal Hall conductivity (ATHC) of −0.14 W/(K·m) at 100 K. Overall, we find that the Fe3−xCoxGaTe2 (x = 0.083, 0.167, 0.250, and 0.330) structures have better anomalous transverse transport performance than the pristine Fe3GaTe2 system and can be used for potential spintronics and spin caloritronics applications. [ABSTRACT FROM AUTHOR]

Improper ferroelectricity and canted ferromagnetism in antiferromagnetically ordered hexagonal ferrites with A2-type spin configuration have been intensely studied due to their potential for room-temperature multiferroicity with strong magnetoelectric couplings. However, the subtle interplay between the magnetic structure and trimer structural distortion, which is a critical ingredient for ferroelectricity, has not been clearly verified in experiments due to the lack of control over trimer distortion. In this study, we report on Lu0.6In0.4FeO3, which exhibits weaker trimer distortion primarily related to the smaller tilting of the FeO5 bipyramids. The reduced vertical displacement of the equatorial oxygen of FeO5 located at the center of the trimer lowers the magnitude of the in-plane Dzyaloshinskii–Moriya vector component, resulting in the absence of canted ferromagnetism with the planar A1-type spin configuration, rather than the canted A2-type observed in other hexagonal ferrites. Our findings demonstrate that the degree of trimer distortion plays an important role in determining the spin configuration in related hexagonal systems. [ABSTRACT FROM AUTHOR]

Improper ferroelectricity and canted ferromagnetism in antiferromagnetically ordered hexagonal ferrites with A2-type spin configuration have been intensely studied due to their potential for room-temperature multiferroicity with strong magnetoelectric couplings. However, the subtle interplay between the magnetic structure and trimer structural distortion, which is a critical ingredient for ferroelectricity, has not been clearly verified in experiments due to the lack of control over trimer distortion. In this study, we report on Lu0.6In0.4FeO3, which exhibits weaker trimer distortion primarily related to the smaller tilting of the FeO5 bipyramids. The reduced vertical displacement of the equatorial oxygen of FeO5 located at the center of the trimer lowers the magnitude of the in-plane Dzyaloshinskii–Moriya vector component, resulting in the absence of canted ferromagnetism with the planar A1-type spin configuration, rather than the canted A2-type observed in other hexagonal ferrites. Our findings demonstrate that the degree of trimer distortion plays an important role in determining the spin configuration in related hexagonal systems. [ABSTRACT FROM AUTHOR]