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Transition metal oxides (TMOs) demonstrate a broad spectrum of properties encompassing electronic correlations, anisotropic transport, magnetism, and optical behavior. The anisotropy arises from both intrinsic crystal symmetry and extrinsic factors like epitaxial strain and structural asymmetry at TMO interfaces. Weiss and Neel's work has elucidated anisotropic magnetic behavior in antiferromagnetic (AFM) materials. AFM TMOs exhibit unique magnetotransport behavior, including weak antilocalization (WAL) and anisotropic magnetoresistance (AMR). Understanding the magnetic structure and band topology in AFM perovskites and their interfaces enables the tailored design of materials for spintronics and energy conversion. In few interfaces lacking inversion symmetry, Rashba spin–orbit coupling (SOC) induces WAL, a quantum correction in conductivity in a two-dimensional electronic system. Electron accumulation and charge transfer across 3d, 5d transition metal-based perovskite interfaces affect WAL and AMR, as observed in 3d/3d and 3d/5d AFM heterostructures, respectively. Advancements in spintronics rely on exploring spin-dependent transport anisotropy. This review focuses on various scattering mechanisms, categorized as extrinsic and intrinsic, in anisotropic transport, particularly in 3d/5d AFM superlattices. The WAL scattering mechanism depends on both intrinsic factors related to Rashba SOC-induced band topology and extrinsic sources like spin impurities and lattice ions. Moreover, the investigation into AMR mechanisms involves the application of impurity-based extrinsic scattering models, which are aligned with the Rashba and Dresselhauss models on Fermi surfaces. This exploration specifically targets the interface of two-band insulators, exemplified by LaAlO3/SrTiO3 and LaVO3/KTaO3. Furthermore, this model achieves comprehensive coverage, extending its applicability to 3d/5d AFM heterostructures like LaMnO3/SrIrO3 and CaMnO3/CaIrO3. Additionally, the intrinsic scattering mechanism tied to Berry phase effects related to band topology is studied, focusing on the CaMnO3/CaIrO3 superlattice. Despite manipulation challenges stemming from reduced stray fields, AFM materials show potential in interface physics and applications within the realm of spintronics. [ABSTRACT FROM AUTHOR]

Magnetic skyrmions are particle-like topological protected spin structures that can be driven by electric current. We demonstrate a single skyrmion-based multilevel data storage device that could also work as the potential artificial synapse for neuromorphic computing. Four pinning sites are designed to situate the skyrmion in selective regions, whose resistances rise owing to the anisotropic magnetoresistance (AMR) induced by the skyrmion. Skyrmion's position could denote the data levels when the device works as a multilevel data storage device. Pinning sites' positions represent the synaptic weights when it functions as the artificial synapse. Multilevel data storage device's data level change or the synapse's potentiation and depression is realized by the electric current applied parallel to the track. Our work shows that the AMR could help to detect a single skyrmion without the magnetic tunnel junction. Moreover, the skyrmion manipulated by pinning provides an approach for precise control and helps realize skyrmion-based in-memory computing. [ABSTRACT FROM AUTHOR]

We report the observation of in-plane anisotropic magnetoresistance (AMR) and planar Hall effect in our recently discovered kagome antiferromagnetic off-stoichiometric single crystal of Mn3Ga. We found that the in-plane AMR is dominated by a sixfold symmetry at low temperature due to the kagome lattice magnetocrystalline anisotropy. However, an unusual fourfold symmetry is also revealed by the angular-dependent AMR measurements, which originates from the little distortion of the crystal accompanying the slight ferromagnetic transition. Moreover, we also found a clear planar Hall effect signal in off-stoichiometric single crystal of Mn3Ga, which may be related to the chiral anomaly, one of the signatures of the magnetic Weyl fermions. [ABSTRACT FROM AUTHOR]

With the interplay between magnetism and topological bands, magnetic kagome semimetals provide promising platforms for exploring exotic correlated electronic states and quantum phenomena such as anomalous Hall effect, quantum spin liquid, and unconventional magnetoresistance, as well as driving advances in electronic and spintronic applications. Here, a field‐induced butterfly‐like anomalous anisotropic magnetoresistance (AMR) effect in an intriguing kagome semimetal Co3In2S2 is reported. The kagome‐lattice Co3In2S2 single crystals are synthesized via a polycrystal‐source chemical vapor transport approach, possessing a high carrier mobility reaching 104 cm2V−1s−1. The Co3In2S2 single crystal exhibits a canted antiferromagnetic state below 5 K, but intriguingly, it is easily transformed into a ferromagnetic state under a small external magnetic field. Furthermore, the planar Hall effect (PHE) is detected, stemming from the complex contribution of field‐induced ferromagnetism and orbital magnetoresistance. Remarkably, as the magnetic field increases, the low‐temperature magnetoresistance behavior of the Co3In2S2 reveals a butterfly‐like AMR effect with a maximum value of 850%, exhibiting a superposition of the two‐, four‐, and six‐fold AMR terms. Band structure calculations suggest that such a field‐induced butterfly‐like AMR effect may originate from the modulations of the electronic structure near the Fermi level by the magnetic moment. The findings offer a valuable platform for understanding the anomalous AMR effect and for the development of advanced spintronic devices. [ABSTRACT FROM AUTHOR]

An alternative way of skyrmion quasi-particle detection is simulated at low voltage bias. The point contact (PC), attached to the strip with a Néel-type skyrmion, can detect it with a higher efficiency than a magnetic tunnel junction. The method is based on detecting the skyrmion via the ballistic magnetoresistance ratio (BRR). PC's resistance with skyrmion significantly differs from the one without it. BRR is estimated in the framework of the point contact model for two directions of spin-polarized current: perpendicular to the transport direction (case 1) and along one (case 2). Skyrmion's size is assumed to be around 3.6 nm in diameter—smaller, or comparable, to the mean free path of electrons, allowing it to utilize the ballistic transport approach. As a result, resistance values for the considered Néel type skyrmion within the related size are estimated as 157 Ω for case 1 and 452.2 Ω for case 2 with optimistic BRR 101.3% and 291.7%, respectively. BRR for case 2 is higher due to the spin-filtering effect. The method also has the potential to detect the skyrmion type, or other magnetic nano structures such as bimeron, domain wall (DW), etc. [ABSTRACT FROM AUTHOR]

Magnetometers with a high sensitivity at weak magnetic fields are desirable for a wide range of sensing applications. Devices that operate on the principle of extraordinary magnetoresistance (EMR) are appealing candidates because of their simplicity and ability to operate at room temperature but they suffer from low sensitivity when compared to state-of-the-art magnetometers such as superconducting quantum interference devices. Since the EMR phenomenon is principally a geometric effect, the shapes of the various parts of the device represent additional degrees-of-freedom which can be manipulated in order to modify the performance of the devices. While previous studies have mostly focused on the inner part of the sensor, in this work, we study the effect of systematically manipulating the shape of the outer boundary. We show that the maximum sensitivity of the device can be increased by 70% by placing a constriction between the voltage or current probes and by 300% if the shape of the boundary is shifted from circular to elliptical. We also show that a finite zero-field sensitivity can be obtained if the horizontal symmetry of the device is broken. These results demonstrate that the outer boundary can have a significant effect on device performance, a finding which paves the way for using shape optimization on the outer boundary for designing sensitive magnetometers. [ABSTRACT FROM AUTHOR]

Angular-dependent magnetoresistance (ADMR) of an epitaxial Fe(001) film is investigated with current along hard and easy axes in-plane at different temperatures. The temperature dependences of ordinary magnetoresistance (OMR), anisotropic magnetoresistance (AMR), and magnetocrystalline anisotropy magnetoresistance (MMR) in ADMR were determined. As temperature decreases, negative OMR and positive AMR with a twofold symmetry show increasing and decreasing amplitudes, respectively. The amplitude of MMR with twofold and fourfold symmetries is almost invariable with both temperature and magnetic field. Meantime, when current was applied at hard and easy axes, MMR contributes an anti-phase signal to ADMR. Our findings of OMR, AMR, and MMR in the Fe(001) ADMR are of great significance to the understanding of magnetoresistance in magnetic films. [ABSTRACT FROM AUTHOR]

The electrical outputs of single-layer antiferromagnetic memory devices relying on the anisotropic magnetoresistance effect are typically rather small at room temperature. Here we report a new type of antiferromagnetic memory based on the spin phase change in a Mn-Ir binary intermetallic thin film at a composition within the phase boundary between its collinear and noncollinear phases. Via a small piezoelectric strain, the spin structure of this composition-boundary metal is reversibly interconverted, leading to a large nonvolatile room-temperature resistance modulation that is two orders of magnitude greater than the anisotropic magnetoresistance effect for a metal, mimicking the well-established phase change memory from a quantum spin degree of freedom. In addition, this antiferromagnetic spin phase change memory exhibits remarkable time and temperature stabilities, and is robust in a magnetic field high up to 60 T. Antiferromagnets have a variety of attractive features such as rapid operation, lack of stray fields, and insensitivity to external perturbations, that make an exciting prospect for memory and computing applications. Unfortunately, readout of the antiferromagnetic state is challenging. Here, Yan, Mao and coauthors demonstrate an antiferromagnet that can be switched between antiferromagnetic phases via piezoelectric strain with a large difference in the resistance between the two antiferromagnetic phases. [ABSTRACT FROM AUTHOR]

A EuZnSb2 antiferromagnetic (AFM) semi metal with a P4/nmm space group (No. 129) is synthesized using the Sb-flux method. The magnetic properties, specific heat, and resistivity of the EuZnSb2 single crystals are analyzed. The magnetic and specific heat properties indicate an antiferromagnetic order of Eu2+ with TN ~ 20 K. The magnetic field is observed to suppress the AFM transition of Eu2+ and the magnetic susceptibility vs. temperature curves exhibit differences when the magnetic field is applied along the ab-plane and c-axis of EuZnSb2 single crystal, reflecting a weak in-plane anisotropy of Eu2+. When the temperature is below 20 K, a spin‒flop transition of the AFM order appears at approximately 1.6 T. The electronic transport measurements indicate that a EuZnSb2 single crystal exhibits metallic properties and an extremely unsaturated positive MR effect. A twofold period of anisotropic magnetoresistance is observed, indicating that the resistivity characteristics correlate with the magnetic field intensity and the angle between the magnetic field direction and the crystallographic axis direction. These studies contribute to enriching the magnetic, specific thermal, and electrical transport properties of EuZnSb2. These results also provide valuable information for further research on other AFM materials. [ABSTRACT FROM AUTHOR]

A EuZnSb2 antiferromagnetic (AFM) semi metal with a P4/nmm space group (No. 129) is synthesized using the Sb-flux method. The magnetic properties, specific heat, and resistivity of the EuZnSb2 single crystals are analyzed. The magnetic and specific heat properties indicate an antiferromagnetic order of Eu2+ with TN ~ 20 K. The magnetic field is observed to suppress the AFM transition of Eu2+ and the magnetic susceptibility vs. temperature curves exhibit differences when the magnetic field is applied along the ab-plane and c-axis of EuZnSb2 single crystal, reflecting a weak in-plane anisotropy of Eu2+. When the temperature is below 20 K, a spin‒flop transition of the AFM order appears at approximately 1.6 T. The electronic transport measurements indicate that a EuZnSb2 single crystal exhibits metallic properties and an extremely unsaturated positive MR effect. A twofold period of anisotropic magnetoresistance is observed, indicating that the resistivity characteristics correlate with the magnetic field intensity and the angle between the magnetic field direction and the crystallographic axis direction. These studies contribute to enriching the magnetic, specific thermal, and electrical transport properties of EuZnSb2. These results also provide valuable information for further research on other AFM materials. [ABSTRACT FROM AUTHOR]

Spin‐polarized donor radicals based on tetrathiafulvalene (TTF) derivatives and nitronyl nitroxide (NN) radicals in which one‐electron oxidation involves the HOMO instead of the SOMO are well known for exhibiting magnetoresistance. In particular, BTBN consists of one dibromo‐TTF and one NN radical, which are linked by a phenyl coupler group. One of the key factors driving magnetoresistance is the presence of intramolecular ferromagnetic (FM) coupling between the oxidized π‐donor (TTF+⋅, D unit) and NN (R unit). Here, a theoretical study is carried out to assess suitable candidates with enhanced FM coupling with respect BTBN, which is thus used as a reference. The study is conducted via in silico chemical modification of the substituents of the BTBN basic functional units (D and R radicals, C coupler) to benefit from the spin polarization mechanism to boost the intramolecular FM coupling, aiming to distort the BTBN radical arrangement within the molecular crystal as little as possible, in the event the material can be synthesized. NICSiso(1) and Wiberg's Bond Order are analyzed to further assist in identifying promising potential candidates, since the decrease in aromaticity is expected to enhance the diradical character and give rise to a larger magnetic coupling value. The most favorable diradical building block to replace the BTBN moiety results from using a hydroxyl‐ethylene (−(H)C=C(OH)−) as a coupler preserving BTBN original radicals, namely, NN and TTF+⋅ units. This study aims at illustrating the feasibility of improving the intramolecular FM interaction between radical moieties, which is fully realized, as a first step towards the synthesis of new materials with (possibly) enhanced magnetoresistance properties. [ABSTRACT FROM AUTHOR]

Magnetic field-induced changes in the electrical resistance of materials reveal insights into the fundamental properties governing their electronic and magnetic behavior. Various classes of magnetoresistance have been realized, including giant, colossal, and extraordinary magnetoresistance, each with distinct physical origins. In recent years, extreme magnetoresistance (XMR) has been observed in topological and non-topological materials displaying a non-saturating magnetoresistance reaching 103−108% in magnetic fields up to 60 T. XMR is often intimately linked to a gapless band structure with steep bands and charge compensation. Here, we show that a linear XMR of 80,000% at 15 T and 2 K emerges at the high-mobility interface between the large band-gap oxides γ-Al2O3 and SrTiO3. Despite the chemically and electronically very dissimilar environment, the temperature/field phase diagrams of γ-Al2O3/SrTiO3 bear a striking resemblance to XMR semimetals. By comparing magnetotransport, microscopic current imaging, and momentum-resolved band structures, we conclude that the XMR in γ-Al2O3/SrTiO3 is not strongly linked to the band structure, but arises from weak disorder enforcing a squeezed guiding center motion of electrons. We also present a dynamic XMR self-enhancement through an autonomous redistribution of quasi-mobile oxygen vacancies. Our findings shed new light on XMR and introduce tunability using dynamic defect engineering. Extreme magnetoresistance is characterized by a large and non-saturating magnetoresistance. Typically, it is observed in materials with compensated bandstructures, however, here, Christensen et al demonstrate a large and non-saturating magnetoresistance in a γAl2O3/SrTiO3 heterostructure, which is related to disorder, rather than the materials bandstructure. [ABSTRACT FROM AUTHOR]

In this study, we analyze the correlation between magnetization and magnetoresistance of perpendicularly anisotropic [Co/Pd] multilayered films with different thicknesses of Pd layers tPd = 0.6–2.0 nm in a wide range of temperatures, T = 4–300 K. We revealed that electron scattering by magnons makes a significant contribution to the magnetoresistance of the multilayers regardless of the layer thickness. Contrary to expectations, the effect of magnon magnetoresistance (MMR) increases with decreasing temperature below T = 50 K in the films with tPd = 0.8 and 1.0 nm. The revealed low-temperature MMR increase, which is most pronounced in the [Co0.5/Pd1.0] multilayers, is associated with the enhanced magnon excitation due to antiferromagnetic exchange coupling between the Co layers. The latter ensures an atypical shape of the magnetization curves of the [Co0.5/Pd1.0] multilayers at low temperatures in a perpendicular magnetic field, which combine a quadratic hysteresis loop of a perpendicularly anisotropic ferromagnet and an anomalous magnetization drop resulting from a violation of the ordering of magnetic moments and their amplified oscillations initiated by the interlayer exchange coupling. [ABSTRACT FROM AUTHOR]

One recent exciting development in the field of magnonics is the discovery of universal unusual anisotropic magnetoresistance (UAMR) in nanometer-thick non-magnetic (NM) metallic bars that are deposited on magnon valves of two ferromagnetic insulators (FIs) sandwiching an NM metal. This UAMR has the same angular dependencies as various bilayers consisting of at least one magnetic layer and at least one metallic layer. This suggests that the UAMR of different systems may originate from the same physics, which is yet to be fully understood. Here, we reveal the common feature shared by all these systems: two-vector dependencies of tensor quantities. Specifically, the resistivity of an NM metallic bar depends on the magnetization of its adjacent FI due to the quantum penetration of itinerant electrons of the metallic bar into the FI and on a perpendicular field at the interface of the bar and the FI. We demonstrate that the two-vector dependence of the resistivity tensor is responsible for the observed universal UAMR of metallic bars on magnon valves, independent of the details of the microscopic interactions in different materials. We also propose experiments that can test this theory. [ABSTRACT FROM AUTHOR]

This paper presents a portable device based on an Anisotropic Magnetoresistance (AMR) sensor for Steel Health Monitoring. The system operates by detecting magnetic anomalies in ferromagnetic materials caused by strain, corrosion, etc. This sensor can have various applications in the transportation, building, and aerospace fields for safety and maintenance monitoring of ferromagnetic materials. In this work, a low-cost device, that combines a high-sensitivity AMR sensor, a microcontroller, and supporting electronics has been designed and implemented. This sensor allows the contactless measurement of the magnetic flux density along three axes, when placed above the material under test, while the microcontroller and the required electronics enable real-time analysis and monitoring of measurements. In order to house and protect the sensor under various circumstances, a 3D-printed enclosure has also been created. This device can be used along with rehabilitation techniques for treatment of defective areas of an under-test material. Its versatility allows it to be employed in a variety of testing conditions for both single-point and scanning mode monitoring. The device's portability, ease of use and applicability to on-site measurements make it accessible to a wide range of users, requiring only a personal computer to display the measurements. Finally, measurements are presented to prove the device's accuracy for steel health monitoring. [ABSTRACT FROM AUTHOR]

We report a first-principles investigation based on density functional theory with the Hubbard U correction to identify the mechanism behind the electric-field modulation, via a - c domain-wall motion, of the anisotropic magnetoresistance (AMR) ratio in C o 2 FeSi / BaTi O 3 heterostructures. The effects of BaTi O 3 (BTO) electric polarization in the [ 001 ], [ 00 1 ¯ ], and [ 0 1 ¯ 0 ] directions on the FeSi / Ti O 2 and CoCo / Ti O 2 interface terminations are taken into account. We show that the response of the interface geometric and electronic properties to the BTO polarization depends on the interface termination. For instance, the pinning of atoms at the FeSi -terminated interface inhibits the [ 001 ] polarization. Through the a - c domain-wall motion, interface hybridized 3 d y z states shift in energy and change the minority-spin density of states at the Fermi level, modifying the AMR through the α = ρ ↓ ρ ↑ component. A discussion of the results based on the Campbell–Fert–Jaoul model with s - s and s - d scattering is provided. The electronic states of C o 2 FeSi inner layers remained mostly unchanged upon the transition between the ferroelectric domains, which indicates that long-range magnetoelastic effects have a negligible influence on the AMR ratio. Hence, the results indicate that interface bonding effects are the origin of the electric-field modulation of the AMR via a - c domain-wall motion in C o 2 FeSi / BaTi O 3 heterostructures. [ABSTRACT FROM AUTHOR]

Anisotropic magnetoresistance (AMR) effect on a Weyl semimetal Co2MnAl Heusler alloy was experimentally and theoretically investigated by changing the Co content, the direction of electric current against the crystal axis, and the measurement temperature. The experimentally fabricated Co2MnAl thin films epitaxially grown on a MgO single-crystal substrate showed the positive AMR ratios independent of the Co content, the direction of electric current, and the measurement temperature. The AMR ratios for the direction of electric current along Co2MnAl[100] were larger than those along Co2MnAl[110]. The maximum AMR ratios for Co2MnAl[100] were 0.576% at 5 K and 0.349% at 300 K for a Co content of 47 at. %, which is close to the stoichiometric composition. Furthermore, the theoretical calculations of AMR ratios based on the s-d scattering process of the electrons at the Fermi energy, including the information on the density of states (DOS) obtained from first-principles calculations, exhibited trends similar to the experimental results. Compared with the AMR results of Co2MnGa[110], we found that the magnitude relation between the partial DOS of the ε and γ orbitals of the d state of Co atoms determined the sign of the AMR ratios. These results suggest that the AMR effect of Weyl semimetal Co2MnAl can be elucidated by the s-d scattering process of the electrons. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms of unidirectional magnetoresistance (UMR) has become an important topic for its potential application of a two-terminal spin–orbit torque device. Field sweep DC measurements have been proposed and adopted to measure the value of UMR instead of second harmonic measurements. In this paper, potential measurement errors in conventional DC measurements are investigated. Oersted field and field-like torque usually do not influence the measurement, but a large field-like torque was found to lead to an anisotropic magnetoresistance difference when the sample is not perfectly aligned with the external field. The existence of ordinary magnetoresistance was also found to contribute to a large background. In this paper, an alternative measurement method for UMR was proposed and demonstrated to address those issues related to previous DC measurements. Our work may broaden the understanding of the error sources of UMR measurements and provide a reliable DC measurement method for the characterization of UMR. [ABSTRACT FROM AUTHOR]

We focus on rare-earth-free anti-perovskite Mn4−xNixN epitaxial films, which can be used for ultrafast current-induced domain wall motion (CIDWM) in magnetic strips. The magneto-transport properties of these materials are very important for a deep understanding of CIDWM. In this study, we investigated the magneto-transport properties of Mn4−xNixN epitaxial films grown on SrTiO3(001) and MgO(001) substrates through anisotropic magnetoresistance (AMR) measurements at temperatures between 2 and 300 K. In samples with a small Ni composition such as x = 0.05−0.1, the AMR ratio of Mn4−xNixN drastically decreased with increasing temperature. We also analyzed the twofold and fourfold symmetries in the AMR curves. Fourfold symmetry is caused by tetragonal crystal fields and is unique to anti-perovskite 3d-metal nitrides such as Mn4N and Fe4N. Only slight fourfold symmetry was observed in Mn4−xNixN. We also performed first-principles calculations with the Vienna ab initio simulation package (VASP) to obtain the projected density of states (PDOS) of d orbitals in Mn4−xNixN, which is responsible for the magnetism of these materials. We conclude that these results are due to the Ni atoms, which function as magnetic impurities and lead to a noticeable change in PDOS, as proved by VASP calculation. [ABSTRACT FROM AUTHOR]

The anomalous Hall effect (AHE) has been widely studied and is well-known in ferromagnetic metals. It is usually investigated in the static regime with the magnetization at equilibrium. In this work, we study the AHE in the dynamic regime where the magnetization is resonantly excited. The microwave-induced ac current and magnetization precession both at GHz frequencies can cooperatively generate a dc voltage. In conventional ferromagnets, this effect, dubbed as resonant AHE (RAHE), is often overwhelmed by other effects such as spin pumping and spin rectification induced by anisotropic magnetoresistance. Here, we observe the RAHE in Co2MnGa, a ferromagnetic Weyl semimetal. In this material, the RAHE dominates over other effects, as observed in angle-dependent measurements. The RAHE in Co2MnGa is an order of magnitude larger than in Permalloy, a conventional ferromagnet. This enhancement is induced by the Berry curvature in the topological band structure of Co2MnGa. The large RAHE demonstrated in this work provides a viable methodology to convert microwave signals into dc voltages for telecommunication applications. [ABSTRACT FROM AUTHOR]

This paper reviews works on the dynamic analysis of flexible and rigid pavements under moving vehicles on the basis of continuum-based plane strain models and linear theories. The purpose of this review is to provide information about the existing works on the subject, critically discuss them and make suggestions for further research. The reviewed papers are presented on the basis of the various models for pavement-vehicle systems and the various methods for dynamically analyzing these systems. Flexible pavements are modeled by a homogeneous or layered half-plane with isotropic or anisotropic and linear elastic, viscoelastic or poroelastic material behavior. Rigid pavements are modeled by a beam or plate on a homogeneous or layered half-plane with material properties like the ones for flexible pavements. The vehicles are modeled as concentrated or distributed over a finite area loads moving with constant or time dependent speed. The above pavement-vehicle models are dynamically analyzed by analytical, analytical/numerical or purely numerical methods working in the time or frequency domain. Representative examples are presented to illustrate the models and methods of analysis, demonstrate their merits and assess the effects of the various parameters on pavement response. The paper closes with conclusions and suggestions for further research in the area. The significance of this research effort has to do with the presentation of the existing literature on the subject in a critical and easy to understand way with the aid of representative examples and the identification of new research areas. [ABSTRACT FROM AUTHOR]

Achieving room-temperature high anisotropic magnetoresistance ratios is highly desirable for magnetic sensors with scaled supply voltages and high sensitivities. However, the ratios in heterojunction-free thin films are currently limited to only a few percent at room temperature. Here, we observe a high anisotropic magnetoresistance ratio of −39% and a giant planar Hall effect (520 μΩ⋅cm) at room temperature under 9 T in β-Ag2Te crystals grown by chemical vapor deposition. We propose a theoretical model of anisotropic scattering — induced by a Dirac cone tilt and modulated by intrinsic properties of effective mass and sound velocity — as a possible origin. Moreover, small-size angle sensors with a Wheatstone bridge configuration were fabricated using the synthesized β-Ag2Te crystals. The sensors exhibited high output response (240 mV/V), high angle sensitivity (4.2 mV/V/°) and small angle error (<1°). Our work translates the developments in topological insulators to a broader impact on practical applications such as high-field magnetic and angle sensors. Achieving room-temperature high anisotropic magnetoresistance ratios is highly desirable for magnetic sensors. Here, the authors observe a high anisotropic magnetoresistance ratio of −39% and a giant planar Hall effect (520 μΩ·cm) at room temperature under 9 T in β-Ag2Te crystals grown by CVD. [ABSTRACT FROM AUTHOR]

Magnetic position sensors have extensive applications in various industrial sectors and consumer products. However, measuring angles in the full range of 0–360° in a wide field range using a single magnetic sensor remains a challenge. Here, we propose a magnetic position sensor based on a single Wheatstone bridge structure made from a single ferromagnetic layer. By measuring the anisotropic magnetoresistance (AMR) signals from the bridge and two sets of anomalous Nernst effect (ANE) signals from the transverse ports on two perpendicular Wheatstone bridge arms concurrently, we show that it is possible to achieve 0–360° angle detection using a single bridge sensor. The combined use of AMR and ANE signals allows a mean angle error in the range of 0.51–1.05° within a field range of 100 Oe–10,000 Oe to be achieved. [ABSTRACT FROM AUTHOR]

Anisotropic magnetoresistance (AMR) sensors are pivotal in various applications due to their low power consumption, scalability, and cost-effectiveness due to the simple sensor structure, comprising one NiFe film, usually encased in a buffer and cap layer. In this work, we explore the effects of inserting MgO and Pt dusting layers between the NiFe sensing layer and adjacent capping and buffer layers, on the electric, magnetic and structural properties of AMR sensors. We describe results on sensors based on Ta/NiFe/Ta, with an as-processed AMR value of 2.0 %. The insertion of Pt thin films had a positive impact, with AMR values increasing to 2.2 %, contrary to the observed with MgO dusting films. Magnetic annealing up to 370 °C caused an increase of the resistivity and reduction in AMR (with Pt dusting layers), on the contrary, MgO dusting layers improved the sensor performance upon annealing, with AMR increasing to 2.5 % (5 h at 370 °C). In light of the findings, the incorporation of Pt and MgO dusting layers enables tailoring the grain size and resistance of Ta/NiFe/Ta films, while combined with proper annealing, which is relevant for applications where Ta and NiFe are available for AMR sensor fabrication. [ABSTRACT FROM AUTHOR]

At present, magnetic induction switches are widely used in industrial automation control and biological sensing systems. A core module composed of a magnetic sensing device and a signal conditioning circuit is designed and analyzed in this paper. Utilizing a permalloy film with the anisotropic magneto-resistance (AMR) effect, the novel magnetic induction switch shows its ability to correctly detect the direction of magnetic fields. Furthermore, an interfacial circuit based on a trans-impedance amplifier (TIA) is designed to measure and regulate the output signal of the sensing device. Accurate simulation results show the gain of the TIA reaches up to 51.36 dB with a bandwidth of 1.3 GHz and a power consumption of 3.65 mW. The outstanding performance of the proposed module demonstrates the possibility of solving the problems induced by high input impedance, high frequency, and parasitic effects in magnetic induction switches. [ABSTRACT FROM AUTHOR]

We report a two-dimensional electron gas created at the (Ga0.5Al0.5)2O3/SrTiO3 heterointerfaces with different deposition temperatures and thicknesses by a pulsed laser deposition method. It is found that the critical deposition temperature for the metal-to-insulator transition is about 400 °C with a thickness of 43.2 nm. The carrier density and mobility of sample at the deposition temperature of 300 °C are 1012 cm−2 and 67.2 cm2 V−1 s−1 at 50 K, respectively. The thickness of the conductive layer is ∼4.0 nm estimated from the anisotropic magnetoresistance. The bandgaps of films deposited at different temperatures are in the range of 5.6–5.9 eV. Furthermore, the heterointerfaces have a strong response to 360 nm light with a relative resistance change of ∼70%. Our results are related to the charge transfer due to the oxygen defect at the interfaces, which provides a way for the development of third-generation semiconductor optoelectronic devices. [ABSTRACT FROM AUTHOR]

The Magnetoelectric Spin‐Orbit (MESO) technology aims to bring logic into memory by combining a ferromagnet with a magnetoelectric (ME) element for information writing, and a spin‐orbit (SO) element for information read‐out through spin‐charge conversion. Among candidate SO materials to achieve a large MESO output signal, oxide Rashba two‐dimensional electron gases (2DEGs) have shown very large spin‐charge conversion efficiencies, albeit mostly in spin‐pumping experiments. Here, all‐electrical spin‐injection and spin‐charge conversion experiments in nanoscale devices harnessing the inverse Edelstein effect of SrTiO3 2DEGs are reported. Nanodevices aredesigned, patterned, and fabricated in which a spin current injected from a cobalt layer into the 2DEG is converted into a charge current. The spin‐charge conversion signal is optimized by applying back‐gate voltages and studied its temperature evolution. It further disentangles the inverse Edelstein contribution from spurious effects such as the planar Hall effect, the anomalous Hall effect, or the anisotropic magnetoresistance. The combination of non‐volatility and high energy efficiency of these devices can potentially lead to new technology paradigms for beyond‐CMOS computing architectures. [ABSTRACT FROM AUTHOR]

Unidirectional magnetic anisotropy induced by exchange bias (EB) between ferromagnetic and antiferromagnetic layers is of paramount importance in various spintronic devices. Traditional setting and optimization of EB involve cooling through the Néel temperature of the antiferromagnets under biasing field in vacuum furnace which takes hours of time and cannot realize localized control of EB. Herein, an alternative process to configure EB by injection of microsecond current impulse for locally heating of the heterostructure is reported. 180‐degree exchange bias switching has been realized in both anisotropic magnetoresistance and giant magnetoresistance units, resulting in tunable magnetic field sensing functionalities. This mechanism for pinpoint control of EB provides more freedom for the design and optimization of various sensing and logic spintronics. [ABSTRACT FROM AUTHOR]

We present a simple implementation of calculation of spin current profiles using a partial differential equation platform. By solving multiple scalar potentials, spin injection, spin/charge inter-conversion, and thermal spin injection phenomena can be well reproduced numerically. As a demonstration, we show spin current generation and detection in a composite of ferromagnetic, spin conducting, and spin-Hall-metallic materials. Furthermore, we present a model extended to three-dimensionally polarized spin current and describe the matrix for spin/charge current inter-conversion in a conductive ferromagnet, which allows for numerical reproduction of anomalous and planar Hall effects. It is found that the planar Hall voltage is in part generated by spin Hall conductivities, though its magnitude is orders smaller than that induced by the anisotropic magnetoresistance. Our method will contribute to further development of effective and feasible simulations of spin-current-mediated systems. [ABSTRACT FROM AUTHOR]

The experimental realization of topological semimetals in the past decade has brought them to the new frontier of condensed matter research. In this paper, we study the angle dependence of the magnetoresistance and planar Hall effect of type-II Dirac semimetal PtTe2 microflakes. The magnetotransport properties of a PtTe2 device are characterized at various temperatures (T = 10–300 K) and different magnetic fields (H = 1–9 T). Remarkable anisotropic magnetoresistance and planar Hall resistance are observed, which can be ascribed to the anisotropic orbital magnetoresistance. Our work provides a comprehensive analysis on the transport properties of PtTe2 and paves the way for its application in the future. [ABSTRACT FROM AUTHOR]

The experimental realization of topological semimetals in the past decade has brought them to the new frontier of condensed matter research. In this paper, we study the angle dependence of the magnetoresistance and planar Hall effect of type-II Dirac semimetal PtTe2 microflakes. The magnetotransport properties of a PtTe2 device are characterized at various temperatures (T = 10–300 K) and different magnetic fields (H = 1–9 T). Remarkable anisotropic magnetoresistance and planar Hall resistance are observed, which can be ascribed to the anisotropic orbital magnetoresistance. Our work provides a comprehensive analysis on the transport properties of PtTe2 and paves the way for its application in the future. [ABSTRACT FROM AUTHOR]

This study investigates the crystal structure, epitaxial relation, and magnetic properties in CoFe thin films deposited on a flexible mica substrate. The epitaxial growth of CoFe thin films was successfully achieved by DC magnetron sputtering, forming three CoFe(002) domains exhibiting four-fold symmetry on the mica substrate. A notable achievement of this work was the attainment of the highest anisotropic magnetoresistance (AMR) value reported to date on a flexible substrate. Additionally, it was observed that the magnetic characteristics of the CoFe films on the flexible mica substrate display reversibility upon strain release. More importantly, the AMR effect of epitaxial CoFe films on flexible mica shows lesser dependence on the crystalline orientation and remains the same under different bending states. These findings demonstrate the potential of utilizing CoFe films on flexible substrates to develop wearable magnetoresistance sensors with diverse applications. [ABSTRACT FROM AUTHOR]

We report the observation of the orbital counterpart of the spin Hall magnetoresistance (SMR): the orbital Hall magnetoresistance (OMR). We measured angular-dependent longitudinal magnetoresistance for Ni/Ti bilayer and Ni single-layer films by rotating a magnetic field along three orthogonal planes. When the magnetic field is rotated in the plane perpendicular to the applied current direction, the angular dependence of the magnetoresistance in the Ni/Ti bilayers is consistent with the prediction of the SMR and OMR, whereas that in the Ni single-layer film can be attributed to the geometrical size effect of the anisotropic magnetoresistance. In the Ni/Ti bilayers, the magnetoresistance ratio is found to be five orders of magnitude larger than the prediction of the SMR, indicating that the OMR plays a dominant role in this system. [ABSTRACT FROM AUTHOR]

We fabricate SrRuO3/PbZr0.52Ti0.48O3 heterostructures each with an in-plane tensile-strained SrRuO3 layer and investigate the effect of an applied electric field on anomalous Hall effect. The four-fold symmetry of anisotropic magnetoresistance and the nonmonotonic variation of anomalous Hall resistivity are observed. By applying positive electric field or negative electric field, the intersecting hump-like feature is suppressed or enhanced, respectively. The sign and magnitude of the anomalous Hall conductivity can be effectively controlled with an electric field under a high magnetic field. The electric-field-modulated anomalous Hall effect is associated with the magnetization rotation in SrRuO3. The experimental results are helpful in modulating the magnetization rotation in spintronic devices based on SrRuO3 heterostructures. [ABSTRACT FROM AUTHOR]

NiCoFeCu films were electrodeposited on Ti substrates at different deposition potentials and different concentrations of saccharin added to solution. Compositional analysis showed that although Ni was the highest concentration in solution at low potentials of −1.0 V and −1.5 V, the Ni content was lower than the Co content in the films. Anomalous co-deposition behaviour of iron group metals was observed. When the deposition potential increased to −2.0 V and −2.5 V, the Ni content of films increased while the Co, Fe and Cu content decreased. In the case of saccharin addition to the solution, there is a slight change in the film content. All films have face-centred cubic structure. Structural analysis clearly showed that the potential has a significant effect on the texture degree of the films, since the crystal texture changed from (111) to (220) with increasing potential. The surface morphology of the films was observed to be affected by the deposition potential and saccharin concentration. For the magnetic analysis, saturation magnetisation, Ms value gradually decreased from 905 to 715 emu/cm3 with the variation of film content caused by the increase of the potential from −1.0 V to −2.5 V. And, a slight increase in Ms was detected with the addition of saccharin. Besides, the longitudinal and transverse magnetoresistance magnitudes increased from ∼2.5 % to 7.0 % with increasing deposition potential and all films exhibit anisotropic magnetoresistance. Films with desired magnetic properties can be obtained for potential use as magnetic materials in electronics such as magnetoresistive devices. [ABSTRACT FROM AUTHOR]

Temperature and magnetic field–dependent electrical and magnetic properties of La1−xCaxMnO3 (x = 0.4, 0.5) polycrystalline materials prepared by the sol-gel method are studied. An apically compressed/elongated-type distorted orthorhombic pnma-O′–phase crystallization occurs in the sample with the addition of Ca. The crystallized phases are ensured by the Rietveld refinement using the Fullprof package. Dangling bonds on the surfaces of the nanosized particles affect the vibrational features. Field emission scanning electron microscopy (FESEM) images depict the agglomeration of uniformly sized grains. With increase of Ca concentration, super-exchange (SE) interactions overcome the dominant double-exchange (DE) interactions and shift the Curie-temperature to a lower value (TC = 267 – 234K). Based on the Banerjee's criterion, the Arrott plot confirms a second-order magnetic phase transition in the samples. Temperature-dependent evolution of the Griffiths-like phase (GP) is observed in the samples and GP% increases with Ca content. The various transitions in the different temperature ranges and magnetic field–dependent electrical transport behaviours are explained using different theoretical models. The dopant concentration influences the Mn3+/Mn4+ ratio, leading to changes in the conductivity, which is mediated by ferromagnetically (FM) ordered conduction channels, altering the metal to insulator (M-I) as well as the ferromagnetic to paramagnetic (FM-PM) as well as the ferromagnetic to antiferromagnetic (FM-AFM) transition temperatures. The electrical transport in the high temperature region is explained using variable range and small polaron hopping (VRH and SPH) models. Using Holstein's relation, it is evident that non-adiabatic SPH (NASPH) model is the most adequate method to explain the high-temperature electrical conductivity. The half-doped samples show a higher value (~ 95%) of magnetoresistance (MR). The present study shows an increase in the Tc and TM − I towards room temperature and in the MR percentage, which may be good for different applications. [ABSTRACT FROM AUTHOR]

Half-metallic Heusler alloys are promising candidates for spintronic applications due to their high spin polarization. However, the spin polarization strongly depends on the atomic composition, which is time-consuming to optimize from various compositional combinations. Here, we demonstrate a high-throughput compositional optimization method for high spin polarization in Co2(Mn, Fe)Ge Heusler alloys by combining composition-spread films and anisotropic magnetoresistance (AMR) measurement. Two types of composition-spread films of polycrystalline Co2(Mn1−xFex)Ge and (Co2Mn0.5Fe0.5)1−yGey are fabricated on SiO2/Si substrates by combinatorial sputtering deposition, followed by post-annealing. The compositional dependence of AMR shows the largest negative AMR ratio of −0.13% and the smallest temperature dependence of the resistance change of AMR for y = 0.25 in the (Co2Mn0.5Fe0.5)1−yGey composition-spread film, suggesting the highest spin polarization and the closest nature to the ideal half-metal at this composition ratio. To verify this, we also develop a new technique to measure the compositional dependence of spin polarization by measuring the spin accumulation signals of nonlocal spin-valve devices fabricated on the composition-spread films and observe the highest spin polarization of 82% for y = 0.24. This confirms a clear qualitative correlation between the large negative AMR ratio and high spin polarization. Our combinatorial method using the composition-spread films and the AMR measurement proves to be a facile way for optimizing the fabrication conditions of half-metallic Heusler alloys with high spin polarization. [ABSTRACT FROM AUTHOR]

We report a study of longitudinal resistivity, anisotropic magnetoresistance (MR), and Hall effect on epitaxial Nd2Ir2O7 (111) thin films grown by the solid phase epitaxy technique, in which spin–orbit coupling, electronic correlation, magnetic frustration, and f-d exchange interaction are present. Temperature-dependent longitudinal resistivity (ρxx) data indicate semimetallic charge transport in the low-temperature region. Field-cooled longitudinal resistivity measurements detect negligible domain-wall conductance compared to the polycrystal or single-crystal samples. Angle-dependent MR measurement shows that the magnetic structure of Ir4+ 5d moments can be finely tuned by applying a magnetic field along different crystallographic directions. MR measurements show a field-induced modification of the Nd3+ 4f spin structure from all-in-all-out/all-out-all-in (AIAO/AOAI) (4-in-0-out) to 1-in-3-out for the applied field (H) along the [111] direction, resulting in field-induced plastic deformation of the Ir4+ domain distribution. In contrast, the application of field (H) along the [001] and [011] directions could not modify any domain distribution. A large spontaneous Hall effect (SHE) signal has been observed on Nd2Ir2O7 (111) thin film with AIAO/AOAI antiferromagnetic ordering for the application of field (H) along [001], [ 1 ̄ 1 ̄ 0], and [111] directions. The appearance of a large spontaneous Hall signal for the applied field along [001] and [ 1 ̄ 1 ̄ 0] directions rules out domain switching as the origin of the Hall effect and confirms the presence of the Weyl semimetallic phase in Nd2Ir2O7 (111) thin films. In addition to SHE, a large topological-like Hall signal is also observed, possibly due to the presence of multiple Weyl nodes in the electronic band structure. [ABSTRACT FROM AUTHOR]

The confluence between high-energy physics and condensed matter has produced groundbreaking results via unexpected connections between the two traditionally disparate areas. In this work, we elucidate additional connectivity between high-energy and condensed matter physics by examining the interplay between spin-orbit interactions and local symmetry-breaking magnetic order in the magnetotransport of thin-film magnetic semimetal FeRh. We show that the change in sign of the normalized longitudinal magnetoresistance observed as a function of increasing in-plane magnetic field results from changes in the Fermi surface morphology. We demonstrate that the geometric distortions in the Fermi surface morphology are more clearly understood via the presence of pseudogravitational fields in the low-energy theory. The pseudogravitational connection provides additional insights into the origins of a ubiquitous phenomenon observed in many common magnetic materials and points to an alternative methodology for understanding phenomena in locally-ordered materials with strong spin-orbit interactions. There are areas where high-energy and condensed-matter physics can successfully overlap a prominent example being topological matter and the role of supersymmetry. Here, via anisotropic magnetoresistance, the authors investigate distortions in the Fermi surface geometry of FeRh films and provide a theoretical interpretation that considers the results within the framework of a pseudogravitational fields. [ABSTRACT FROM AUTHOR]

Spin–orbit coupling and breaking of inversion symmetry are necessary ingredients to enable a pure spin current-based manipulation of the magnetization via the spin–orbit torque effect. Currently, magnetic insulator oxides with non-dissipative characteristics are being explored. When combined with non-magnetic heavy metals, known for their large spin–orbit coupling, they offer promising potential for energy-efficient spin-orbitronics applications. The intrinsic electronic correlations characterizing those strongly correlated oxides hold the promises to add extra control-knobs to the desired efficient spin-wave propagation and abrupt magnetization switching phenomena. Spinel vanadate FeV2O4 (FVO) exhibits several structural phase transitions, which are accompanied by an intricate interplay of magnetic, charge, and orbital orderings. When grown as a thin film onto SrTiO3, the compressive strain state induces a perpendicular magnetic anisotropy, making FVO-based heterostructures desirable for spin-orbitronics applications. In this study, we have optimized the deposition of stoichiometric and epitaxial Pt/FVO heterostructures by pulsed laser deposition and examined their spin-related phenomena. From angle-dependent magnetotransport measurements, we observed both anisotropic magnetoresistance and spin Hall magnetoresistance (SMR) effects. Our findings show the SMR component as the primary contributor to the overall magnetoresistance, whose high value of 0.12% is only comparable to properly optimized oxide-based systems. [ABSTRACT FROM AUTHOR]

Electric field control of magnetism through nanoionics has attracted tremendous attention owing to its high efficiency and low power consumption. In solid-state dielectrics, an electric field drives the redistribution of ions to create one-dimensional magnetic conductive nanostructures, enabling the realization of intriguing magnetoresistance (MR) effects. Here, we explored the electric-controlled nickel and oxygen ion migration in Pt/HfO2− x /NiO y /Ni heterojunctions for MR modulation. By adjusting the voltage polarity and amplitude, the magnetic conductive filaments with mixed nickel and oxygen vacancy are constructed. This results in the reduction of device resistance by ∼103 folds, and leads to an intriguing partial asymmetric MR effect. We show that the difference of the device resistance under positive and negative saturation magnetic fields exhibits good linear dependence on the magnetic field angle, which can be used for magnetic field direction detection. Our study suggests the potential of electrically controlled ion migration in creating novel magnetic nanostructures for sensor applications. [ABSTRACT FROM AUTHOR]

In this report, peculiarities of magnetoresistive properties of nanostructured (Ni80Fe20)xAu1-x thin films containing from 10 to 60 at.% of Au were investigated. We focus on the samples with a thickness of 45 nm fabricated by the method of electron-beam co-evaporation. The influence of Au atoms concentration and the annealing process within the temperature range from 300 to 700 K on the microstructure, magnitude, and nature of magnetoresistive effects has been discussed. The analysis of electronographic studies showed that both face-centered cubic Ni3Fe and Au phases are visible in the diffraction images. Upon varying thin film compositions and annealing conditions, the phase state does not change. At the same time, magnetoresistive properties of thin films demonstrated a strong dependence on both the concentration of sample components and annealing conditions. Samples after deposition showed typical giant magnetoresistance behavior at 20-46 at.% of Au, which is also typical for samples annealed at 400 and 500 K. The transition to the anisotropic nature of magnetoresistance occurs upon annealing at 500 K. [ABSTRACT FROM AUTHOR]

The ExoMars programme has the objective to answer to the question of whether life ever existed on Mars. The second mission comprising the Rosalind Franklin rover and Kazachok Surface Platform was designed to focus specifically on the characterization of the environmental parameters which can play an important role for the existence of life on the surface of the planet. One of these parameters is the magnetic field because of its ability of shielding the solar and cosmic radiation. For such characterization, the scientific suite of the Surface Platform counts with two instruments: the Anisotropic MagnetoResistance (AMR) and the MArtIan Ground ElectromagneTic (MAIGRET) instruments. The AMR goal is to characterize both the surface and subsurface and the time-varying magnetic fields, related to the crustal and the external fields respectively, at the ExoMars landing site in Oxia Planum. The operation to achieve these goals includes two phases, the first phase corresponding to the lander descent and the second phase in which the instrument is deployed on the surface. In this work, we simulate the first operations phase using synthetic magnetic field models, assuming that the different crustal units at the landing site might be magnetized. We also perform measurements in our laboratory to simulate the second phase operation of the instrument on the Martian surface. We discuss the capability of interpretation of the instrument, based on the available information of the landing site and the results from our models. [ABSTRACT FROM AUTHOR]

Control over the movements of free charge carriers across any manganite based interface can functionalize the device for spintronic applications. This can be achieved through external stimuli that alter various electronic phases of manganites having comparable energy levels. In the present communication, the LaMnO3/La0.7Ca0.3MnO3/LaAlO3 (LMO/LCMO/LAO) manganite–manganite structure was successfully fabricated using a cost effective chemical solution deposition (CSD) method. Field effect configuration was employed to understand the interface resistive nature of the LMO/LCMO interface for which externally applied interface electric fields have been applied across the same interface. The applied interface electric field considerably affects the LMO/LCMO interface resistivity which has been discussed in the context of free charge carrier movements across the same interface. The state of the spin fluctuations across manganite lattices has been recognized by fitting the resistivity behavior theoretically using the Zener double exchange (ZDE) polynomial law. Complex electroresistance (ER) and anisotropic magnetoresistance (AMR) behaviors have been discussed in detail for understanding the electrical nature of the LMO/LCMO interface under different applied stimuli. [ABSTRACT FROM AUTHOR]

Antiferromagnetic spintronics exploits unique properties of antiferromagnetic materials to create new and improved functionalities in future spintronic applications. Here, we briefly review the experimental efforts in our group to unravel spin transport properties in antiferromagnetic materials. Our investigations were initially focused on metallic antiferromagnets, where the first evidence of antiferromagnetic spin-transfer torque was discovered. Because of the lack of metallic antiferromagnets, we then shifted towards antiferromagnetic Mott insulators, where a plethora of transport phenomena was found. For instance, we observed a very large anisotropic magnetoresistance, which can be used to detect the magnetic state of an antiferromagnet. We also observed reversible resistive switching and now provide unequivocal evidence that the resistive switching is associated with structural distortions driven by an electric field. Our findings support the potential of electrically controlled functional oxides for various memory technologies. [ABSTRACT FROM AUTHOR]

Antiferromagnetic (AFM) iridates are recently discovered to be a fertile playground for exploring emergent phenomena relevant to the intriguing interplay among multiple degrees of freedom, such as strong spin–orbit coupling, electron correlation, and the crystal field effect. These phenomena offer interesting routes for probing as well as controlling AFM order in iridate, which is essential in AFM spintronics. In this perspective, we will briefly review recent studies on AFM iridates that host large potential for advancing the reading (anisotropic magnetoresistance effect, etc.) and writing (magnetic field control of AFM order, etc.) functionalities of AFM spintronics. We will also discuss promising directions for expanding the research of AFM iridate based spintronics from the perspectives of material growth, manipulation protocol, and characterization technique. [ABSTRACT FROM AUTHOR]

The electrical transport properties of rare-earth tritelluride TbTe3 are investigated at low temperatures and high magnetic fields. The chargedensity- wave and anti-ferromagnetic transition are found at 334 K (340 K) and 6.0 K (9.4 K) for bulk TbTe3 (thin device), respectively. An extremely large and non-saturating magnetoresistance (MR) as high as 5600% is detected under a perpendicular magnetic field at 1.8 K and 9 T. Furthermore, angular-dependent transport measurements reveal obvious anisotropic MR behaviors in both bulk TbTe3 and thin devices. Moreover, in the thin TbTe3 device, exotic linear MR at low temperatures is observed in all field directions. Hall measurements are also performed, and the quantitative fitting of the two-band model to longitudinal and Hall conductivity of the TbTe3 device reveals two types of carriers (hole and electron). Our work may stimulate interests of layered rare-earth tritellurides in fundamental physics and potential technological applications. [ABSTRACT FROM AUTHOR]

The electrical transport properties of rare-earth tritelluride TbTe3 are investigated at low temperatures and high magnetic fields. The chargedensity- wave and anti-ferromagnetic transition are found at 334 K (340 K) and 6.0 K (9.4 K) for bulk TbTe3 (thin device), respectively. An extremely large and non-saturating magnetoresistance (MR) as high as 5600% is detected under a perpendicular magnetic field at 1.8 K and 9 T. Furthermore, angular-dependent transport measurements reveal obvious anisotropic MR behaviors in both bulk TbTe3 and thin devices. Moreover, in the thin TbTe3 device, exotic linear MR at low temperatures is observed in all field directions. Hall measurements are also performed, and the quantitative fitting of the two-band model to longitudinal and Hall conductivity of the TbTe3 device reveals two types of carriers (hole and electron). Our work may stimulate interests of layered rare-earth tritellurides in fundamental physics and potential technological applications. [ABSTRACT FROM AUTHOR]

Spin–orbit-torque-driven dynamics have recently gained interest in the field of magnetism due to the reduced requirement of current densities and an increase in efficiency, as well as the ease of implementation of different devices and materials. From a practical point of view, the low-frequency dynamics below 1 GHz is particularly interesting since dynamics associated with magnetic domains lie in this frequency range. While spin-torque excitation of high-frequency modes has been extensively studied, the intermediate low-frequency dynamics have received less attention, although spin torques could potentially be used for both manipulation of the spin texture and the excitation of dynamics. In this work, we demonstrate that it is possible to drive magnetic vortex dynamics in a single microdisk by spin-Hall torque at varying temperatures and relate the results to transport properties. We find that the gyrotropic mode of the core couples to the low-frequency microwave signal and produces a measurable voltage. The dynamic measurements are in agreement with magnetic transport measurements and are supported by micromagnetic simulations. Our results open the door for integrating magnetic vortex devices in spintronic applications. [ABSTRACT FROM AUTHOR]