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A phase transformation model based on magnetization is proposed in this paper, which accurately tracks the change in the phase transformation volume fraction with time/temperature f-T/t by analyzing phase transformation magnetization curves under a magnetic field. This allows for the determination of kinetic parameters related to the nucleation and growth processes such as the phase transformation rate df/dt-T/t and Avrami exponent n, enabling quantitative analysis of phase transformation kinetics under magnetic field effects. Additionally, the phase transformation magnetization under a magnetic field can be accurately fitted by combining the volume fraction calculation model with the Johnson–Mehl–Avrami equation, thus also obtaining the kinetics parameters. The aforementioned two models are applied to study the isothermal and isokinetic transformations of austenite (γ) to ferrite (α) in Fe-1 wt. %Cu alloys, demonstrating the effects of external conditions through variations in kinetic parameters. [ABSTRACT FROM AUTHOR]

This research paper presents systematic micromagnetic modeling of dynamic spin solitons carried by perpendicular magnetization component on a topologically preserved chiral sequence of uniform 360° in-plane domain walls with fixed boundaries in a strip. The long, narrow strip of a soft, magnetic thin film has a repeated in-plane magnetization pattern such that the local magnetization will rotate uniformly in a single chirality, either clockwise or counterclockwise, when moving along the strip in one direction at a constant speed. As spins in an excited soliton precess around its local magnetization field, the exchange interaction with the underlying chiral magnetization configuration yields a linear soliton motion with the direction determined by the handedness of precession and the underlying magnetization chirality. The local hyperbolic secant-like soliton profile holds its shape and energy when traveling without damping, continually changes its shape, and decays otherwise. [ABSTRACT FROM AUTHOR]

Field-free spin–orbit torque switching in synthetic antiferromagnets (SAF) holds significant promise for high-density spintronic memory and logic devices. In this paper, we realize the field-free magnetization switching in SAFs due to the local ion implantation-induced 45° lateral interface and symmetry breaking. Moreover, the magnetization switching ratio is enlarged by the lateral interface owing to the superimposition of a damping-like effective field and a symmetry-breaking effective field. Our work is significant for the development of magnetic random-access memory technology with high-speed and anti-interference ability. [ABSTRACT FROM AUTHOR]

Spin–orbit torque magnetic random-access memory (SOT-MRAM) has received extensive interest in the memory industry. Recent works have focused on a heavy metal (HM)/ferromagnet bilayer with an additional HM capping strip to deterministically switch the magnetization. This paper investigates the switching behaviors of SOT-MRAM utilizing this structure with micromagnetic simulations coupled to the drift-diffusion spin transport model. The mechanism is attributed to the non-negligible negative z-component from spin accumulation on the bottom HM interface, which originates from the associated accumulation at the edges of the HM capping strip. Moreover, device parameters are shown as crucial for deterministic switching and lower power consumption. This study provides fundamental insights into deterministic switching for SOT-MRAM with an additional HM capping strip, which can be readily adopted into practical applications. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate that V0.027Bi0.973TeI, a material with both giant bulk Rashba effect and ferromagnetism, can reverse its magnetization by self-generated spin–orbit torque. Through first-principles calculation, it is found that the giant bulk Rashba effect arises from both bulk space inversion asymmetry and strong spin–orbital coupling, while the ferromagnetism originates from the itinerant d-electrons of doped element vanadium. More importantly, its field-like spin–orbit torque efficiency is determined to be as high as 4.53 × 10−4 mT/(A cm−2), which is more than two orders of magnitude higher than that typically observed in magnetic heterostructures. It is further shown that by using such magnetic bulk Rashba material to form a homogenous spintronic device, the power consumption for magnetization switching can be significantly reduced. [ABSTRACT FROM AUTHOR]

All-optical switching (AOS) of magnetization by a single femtosecond laser pulse in Co/Gd based synthetic ferrimagnets is the fastest magnetization switching process. On the other hand, He ion irradiation has become a promising tool for interface engineering of spintronic material platforms, giving rise to significant modification of magnetic properties. In this paper, we explore the use of He ion irradiation to enhance single pulse AOS of Co/Gd bilayer-based synthetic ferrimagnets. The intermixing of the constituent magnetic layers by He ion irradiation was both numerically simulated and experimentally verified. We theoretically modeled the effects of intermixing on AOS using the layered microscopic 3-temperature model and found that AOS is enhanced significantly by breaking the pristine Co/Gd interface through intermixing. Following this notion, we studied the threshold fluence of AOS as a function of He ion irradiation fluence. We found that the AOS threshold fluence can be reduced by almost 30%. Our study reveals the control of AOS by He ion irradiation, which opens up an industrially compatible approach for local AOS engineering. [ABSTRACT FROM AUTHOR]

A femtosecond laser pulse is able to switch the magnetic state of a 3d-4f ferrimagnetic material on a pico-second timescale. Devices based on this all-optical switching (AOS) mechanism are competitive candidates for ultrafast memory applications. However, a large portion of the light energy is lost by reflection from the metal thin film as well as transmission to the substrate. In this paper, we explore the use of dielectric coatings to increase the light absorption by the magnetic metal layer based on the principle of constructive interference. We experimentally show that the switching energy oscillates with the dielectric layer thickness following the light interference profile as obtained from theoretical calculations. Furthermore, the switching threshold fluence can be reduced by at least 80% to 0.6 mJ/cm2 using two dielectric SiO2 layers sandwiching the metal stack, which scales to 15 fJ of incident energy for a cell size of 502 nm2. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate the ferroelectric gate control of Rashba–Dresselhaus spin–orbit coupling (R–D SOC) in a hybrid heterostructure consisting of a ferromagnetic semiconductor channel (Zn, Co)O(0001) and a ferroelectric substrate PMN-PT(111). The R–D SOC causes a transverse spin current via the charge-spin conversion, which results in unbalanced transverse spin and charge accumulations due to the spin-polarized band in the ferromagnetic (Zn, Co)O channel. By the reversal of gated ferroelectric polarization, we observed 55% modulation of the R–D SOC correlated Hall resistivity to the magnetization correlated anomalous Hall resistivity and 70% modulation of the low-field magnetoresistance at 50 K. Our experimental results pave a way toward semiconductor-based spintronic-integrated circuits with an ultralow power consumption in ferromagnetic semiconductors. [ABSTRACT FROM AUTHOR]

This paper studies spin–orbit torque (SOT) switching behaviors in synthetic antiferromagnet (SyAF) structures of Ta/[Pt/Co]m/Ru/[Co/Pt]n, which are asymmetric between the upper multilayer (UML) and the bottom multilayer (BML). The SOT-induced magnetization switching loops show multiple transitions of switching orientations between clockwise and anticlockwise with an increasing in-plane magnetic field, determined by the effects of the Dzyaloshinskii–Moriya interaction from both the BML and UML in the different stacking structures. Moreover, the field-free SOT switching was observed in the structure of Ta/[Pt/Co]3/Ru (0.5)/[Co/Pt]4. It can be attributed to the horizontal component of magnetic moments in its UML acting as an equivalent field. Therefore, the SyAF structures could be potential candidates for the future SOT-based spintronic devices. [ABSTRACT FROM AUTHOR]

Spin-orbit torque (SOT) has been proposed as an alternative writing mechanism for the next-generation magnetic random access memory (MRAM), due to its energy efficiency and high endurance in perpendicular magnetic anisotropic materials. However, the three-terminal structure of SOT-MRAM increases the cell size and consequently limits the feasibility of implementing high density memory. Multilevel storage is a key factor in the competitiveness of SOT-MRAM technology in the nonvolatile memory market. This paper presents an experimental characterization of a multilevel SOT-MRAM cell based on a perpendicularly magnetized Ta/CoFeB/MgO heterostructure and addresses the initialization-free issue of multilevel storage schemes. Magneto-optical Kerr effect microscopy and micromagnetic simulation studies confirm that the multilevel magnetization states are created by changing a longitudinal domain wall pinning site in the magnet. The realization of robust intermediate switching levels in the commonly used perpendicularly magnetized Ta/CoFeB/MgO heterostructure provides an efficient way to switch magnets for low-power, high-endurance, and high-density memory applications. [ABSTRACT FROM AUTHOR]

Magnetic storage and magnetic memory have recently shifted towards the use of magnetic thin films with large perpendicular magnetic anisotropy (PMA) to simultaneously satisfy the requirements in storage density and thermal stability. Understanding the magnetic switching process and its dependence on the Gilbert damping (α) of materials with large PMA is crucial for developing low-power consumption, fast-switching, and high-thermal stability devices. The need to quantify α of materials with large PMA has resulted in the development of the all-optical ultrafast Time-Resolved Magneto-optical Kerr Effect (TR-MOKE) technique. While TR-MOKE has demonstrated its capability of capturing magnetization dynamics of materials with large PMA, a quantitative analysis regarding the operational optimization of this emerging technique is still lacking. In this paper, we discuss the dependence of the TR-MOKE signal on the magnitude and angle of the applied field, by utilizing a numerical algorithm based on the Landau-Lifshitz-Gilbert equation. The optimized operational conditions that produce the largest TR-MOKE signals are predicted. As an experimental verification, we conduct TR-MOKE measurements on a representative sample of a tungsten-seeded CoFeB PMA thin film to show the excellent agreement of the model prediction with measurements. Our analysis results in a better understanding of the external field influence on the magnetization precession processes. The results of this work can also provide guidance on selecting operational conditions of the TR-MOKE technique to achieve optimal signal-to-noise ratios and thus more accurate measurements of magnetization dynamics. [ABSTRACT FROM AUTHOR]

Grain-to-grain Curie temperature (Tc) variation in media reduces the signal-to-noise ratio due to its contribution to the transition jitter noise, especially when the average grain size is decreased to increase the area storage capacity. Thermally insulating magnetic grain boundaries may suppress such grain-to-grain Tc variation, especially at small grain sizes. In this paper, we discuss the effect of adding a thermally insulating magnetic oxide, in particular, BaFexOy, to the grain boundaries of granular FePt-C heat-assisted magnetic recording media. It is found that BaFexOy is chemically inert with respect to FePt and the chemical ordering of FePt-BaFexOy-C media is similar to that of FePt-C media. By tuning the volume fraction of BaFexOy and C, well-separated FePt grains (average grain size = 6.8 nm) surrounded by BaFexOy shells enable the attainment of perpendicular Hc greater than 35 kOe. Chemical mapping by transition electron microscopy shows that the magnetic oxide appears to be crystalline and completely surrounds the FePt grains. Temperature-dependent magnetization measurements indicate an effective increase in the magnetic grain size at temperatures below the FePt Curie temperature. The pulsed laser pump-probe measurement indicates a measurable reduction of the Curie temperature variation for the FePt-BaFexOy-C media compared to the reference FePt-C media. [ABSTRACT FROM AUTHOR]

This paper describes our proposed measurement technique for the magnetization dynamics in thin films, which employs a microstripe line probe to detect ferromagnetic resonance (FMR) spectra for a film sample either with or without tensile stress. By measurement of FMR frequency shifts using Lorentzian fits to the FMR spectra for a film with and without tensile stress, saturation magnetostriction (λs) can be determined. The measured values were compared with those estimated by the optical cantilever method using the same samples in good agreement. At the same time, a Gilbert damping constant (α) was determined using both the FMR frequency and the FMR linewidth for the tensile stress free film. The results of the experiment demonstrate that our proposed measurement technique allows for more precise evaluation of magnetization dynamics by providing information on both α and λs simultaneously for an individual sample. [ABSTRACT FROM AUTHOR]

One essential feature in magnetic random access memory cells is the spin torque efficiency, which describes the ratio of the critical switching current to the energy barrier. In this paper, it is reported that the spin torque efficiency can be improved by a factor of 3.2 by the use of a dual free layer device, which consists of one layer with perpendicular crystalline anisotropy and another layer with in-plane crystalline anisotropy. Detailed simulations solving the spin transport equations simultaneously with the micromagnetics equation were performed in order to understand the origin of the switching current reduction by a factor of 4 for the dual layer structure compared to a single layer structure. The main reason could be attributed to an increased spin accumulation within the free layer due to the dynamical tilting of the magnetization within the in-plane region of the dual free layer. [ABSTRACT FROM AUTHOR]

This paper reports a bioassay of alpha-fetoprotein (AFP) concentration achieved via the measurement of blocking temperature (TB). Biofunctionalized magnetic nanoparticles (BMNs) consisting of anti-alpha-fetoprotein coated onto dextran-coated magnetic nanoparticles composed of Fe3O4 were prepared and then conjugated with AFP biotargets. It was found that both the saturation magnetization and value of TB increased with the concentration of the associated AFP. Furthermore, the dependence of TB of the samples on magnetic field agreed with the interparticle interaction model. Thus, this study demonstrated a platform to detect biomarkers by characterizing TB with a sensitivity limit of 20 ppb of AFP. The promising results obtained for this bioassay can be attributed to the interparticle interactions and Neel motions of magnetic moments in the BMNs. [ABSTRACT FROM AUTHOR]

Separating particles, which can be either biological or synthetic, in a continuous label-free manner is essential to many applications. Magnetic separation has several advantages over other fielddriven particle separation techniques. It, however, has been limited primarily to situations where particles differ in size or magnetization. We demonstrate in this paper a continuous-flow separation of equal-volumed spherical and peanut-shaped diamagnetic particles in a dilute ferrofluid. This separation is attributed to the shape-dependent magnetophoretic motion, which is the combined result of the shape dependences of the magnetic force and viscous drag. We also develop a threedimensional numerical model to understand this shape-based diamagnetic particle separation and predict the effects of the determining factors. [ABSTRACT FROM AUTHOR]

Cu2O nanoporous films are deposited on porous anodic alumina (PAA) substrates by DC-reactive magnetron sputtering. This paper focuses on voltage driven magnetization switching in Cu2O/PAA (CP) composite films prepared by DC-reactive magnetron sputtering. By applying a dc electric field, the magnetization of the CP composite films can be controlled in a reversible and reproducible way and shows an analogous on-off behavior. The magnitude of the change in the magnetization was about 75 emu/cm3 as the electric field was switched on and off. Resistive switching behavior was also observed in as-prepared CP composite films. Further analysis indicated that the formation/rupture of conducting filaments composed of oxygen vacancies is likely responsible for the changes in the magnetization as well as in the resistivity. Such reversible change of magnetization controlled by an electric field at room temperature may have applications in spintronics and power efficient data storage technologies. [ABSTRACT FROM AUTHOR]

This paper presents experimental results showing that continuous negative ion extraction, without co-extracted electrons, is possible from highly electronegative SF6 ion-ion plasma at low gas pressure (1 mTorr). The ratio between the negative ion and electron densities is more than 3000 in the vicinity of the two-grid extraction and acceleration system. The measurements are conducted by both magnetized and non-magnetized energy analyzers attached to the external grid. With these two analyzers, we show that the extracted negative ion flux is almost electron-free and has the same magnitude as the positive ion flux extracted and accelerated when the grids are biased oppositely. The results presented here can be used for validation of numerical and analytical models of ion extraction from ion-ion plasma. [ABSTRACT FROM AUTHOR]

This paper develops a self-biased magnetoelectric (ME) heterostructure FeCuNbSiB/Terfenol-D/ Be-bronze/Pb(Zr,Ti)O3 (PZT) by sandwiching a nonmagnetic elastic Be-bronze plate between an piezoelectric PZT plate and a magnetization-graded FeCuNbSiB/Terfenol-D layer. The Be-bronze plate severs as the resonance frequency determining element of the ME heterostructure. By using the magnetization-graded magnetostrictive layer and the elastic Be-bronze plate, seven large peaks of ME response with magnitudes of 0.3-10 (V/cm Oe) in 1-70 kHz range are observed at zerobiased magnetic field. This demonstrates that the proposed multi-peak self-biased heterostructure may be useful for multifunctional devices such as multi-frequency energy harvesters or lowfrequency ac magnetic field sensors. [ABSTRACT FROM AUTHOR]

This paper develops a self-biased magnetoelectric (ME) heterostructure FeCuNbSiB/Ni-PZTFeCuNbSiB/ Ni (FN-P-FN) by bonding magnetization-graded FeCuNbSiB/Ni layers at the free ends of piezoelectric Pb(Zr,Ti)O3 (PZT) plate. By using the magnetization-graded magnetostrictive layer and end-bonding heterostructure, giant self-biased ME responses and obvious hysteresis are observed in FN-P-FN heterostructure. The experimental results show that the zero-biased ME voltage coefficient of FN-P-FN heterostructure reaches ~183.2 (V/cm Oe), which is ~2.1, ~4.5, and ~41.6 times higher than that of FeCuNbSiB/Ni/PZT, Ni-PZT-Ni, and FeCuNbSiB-PZTFeCuNbSiB composites, respectively. The results indicate that the proposed three-phase end-bonding heterostructure shows promising applications for high-sensitivity self-biased magnetic field sensors and ME transducers. [ABSTRACT FROM AUTHOR]

In this paper, we use simultaneous magnetometry and electrical transport measurements to critically examine ways in which the Curie temperature (TC) values have been determined in studies of dilute magnetic semiconductors. We show that, in sufficiently homogeneous samples, TC can be accurately determined from remanent magnetization and magnetic susceptibility and from the positions of the peak in the temperature derivative of the resistivity. We also show that the peak of the resistivity does not occur at TC, as illustrated by a (Ga,Mn)As sample for which the peak of the resistivity is at 213±1K when TC is only 178±1K. [ABSTRACT FROM AUTHOR]

This paper reports the interfacial oxygen migration effect and its induced magnetic anisotropy evolution in Pt/Co/MgO/Pt films. During depositing the MgO layer, oxygen atoms from the MgO combine with the neighboring Co atoms, leading to the formation of CoO at the Co/MgO interface. Meanwhile, the films show in-plane magnetic anisotropy (IMA). After annealing, most of the oxygen atoms in CoO migrate back to the MgO layer, resulting in obvious improvement of Co/MgO interface and the enhancement of effective Co-O orbital hybridization. These favor the evolution of magnetic anisotropy from IMA to perpendicular magnetic anisotropy (PMA). The oxygen migration effect is achieved by the redox reaction at the Co/MgO interface. On the contrary, the transfer from IMA to PMA cannot be observed in Pt/Co/Pt films due to the lack of interfacial oxygen migration. [ABSTRACT FROM AUTHOR]

We systematically probed the dynamics of two-dimensional Ni80Fe20 nanowire arrays with different strengths of interwire interactions using angular dependent microwave absorption spectroscopy. The experimental results are analyzed in terms of a graphical representation of the resonant absorption data through a critical-curve-like approach. This representation has the advantage of offering a direct and complete visual representation of anisotropy, interactions, and magnetization dynamics effects in nanomagnet arrays. In the paper, the connection between the proposed image of polar resonant absorption curves and the static switching field critical curves is substantiated using both macrospin and fully micromagnetic simulation approaches. [ABSTRACT FROM AUTHOR]

This paper describes a comprehensive micromagnetic model for the observed complex magnetic domains structures in amorphous wires with positive and negative magnetostriction with or without a glass cover. Many experimental studies and theoretical analysis have suggested several typical domain structures. We show the results of micromagnetic simulations that cover many of these observed data using a single set of physical hypotheses. [ABSTRACT FROM AUTHOR]

This paper reports experimental observations of partial and reversible out-of-plane magnetization change in a thin film Ni/[Pb(Mn1/3Nb2/3)O3]0.68-[PbTiO3]0.32 (001) heterostructure. Electric-field-induced isotropic in-plane compressive strain (∼1000 ppm) eliminates the stripe domain pattern in a 60-nm-thick Ni thin film. When the electric field is removed, the stripe domains are returned to their original configurations with some domain wall pinning perturbations due to ferroelectric domain texturing. The observed domain structure change is attributed to the transition from Bloch wall to Néel wall and the broadening of the Bloch wall. This out-of-plane magnetization change does not occur in thicker (100-nm-thick) Ni thin film. [ABSTRACT FROM AUTHOR]

Spectral line intensity variation is found to be irreversible in circulatory plasma magnetization process by experiments described in this paper, i.e., the curves illustrating spectral line photon fluxes irradiated from a light source immerged in a magnetic field by increasing the magnetic induction cannot be reproduced by decreasing the magnetic induction within the errors. There are two plasma magnetization patterns found. One shows that the intensities are greater at the same magnetic inductions during the magnetic induction decreasing process after the increasing, and the other gives the opposite effect. This reveals that the magneto-induced excitation and de-excitation process is irreversible like ferromagnetic magnetization. But the two irreversible processes are very different in many aspects stated in the text. [ABSTRACT FROM AUTHOR]

This study investigates the interaction between transverse head-to-head domain walls (THHDWs) in permalloy nanowires and magnetostatic charges located within a tripod structure in close proximity. This interaction enables remote pinning of the THHDW. Eight different interactions are measurable, depending on the initialising field sequence. The pinning strengths of an attractive potential well and a repulsive barrier are compared in this paper. Based on experimental measurements, micromagnetic simulations, and a monopolar analytical model, we demonstrate that pinning strength depends on the inhomogeneous charge distribution within the tripod and the relative orientation of the THHDW which faces the tripod. [ABSTRACT FROM AUTHOR]

This paper reports fabrication of 2-nm-thick L10 FePt films at a low substrate temperature of 400 °C using composite MgO and FeAl buffer layers on (001) MgO substrates. The FeAl buffer layer is crucial in promoting the ordered L10 growth of (001) FePt by allowing additional heat uptake. The MgO buffer layer prevents interlayer diffusion of FeAl into the FePt films and induces (001) texture growth. The deposited FePt films consist of isolated nanograins about 13 nm in size. These films have (001) texture and perpendicular magnetic anisotropy with a coercivity of up to 19 kOe. They have potential applications in perpendicular magnetic recording. [ABSTRACT FROM AUTHOR]

In this paper we demonstrate that permalloy (Py), a widely used Ni/Fe alloy, forms contacts to carbon nanotubes (CNTs) that meet the requirements for the injection and detection of spin-polarized currents in carbon-based spintronic devices. We establish the material quality and magnetization properties of Py strips in the shape of suitable electrical contacts and find a sharp magnetization switching tunable by geometry in the anisotropic magnetoresistance (AMR) of a single strip at cryogenic temperatures. In addition, we show that Py contacts couple strongly to CNTs, comparable to Pd contacts, thereby forming CNT quantum dots at low temperatures. These results form the basis for a Py-based CNT spin-valve exhibiting very sharp resistance switchings in the tunneling magnetoresistance, which directly correspond to the magnetization reversals in the individual contacts observed in AMR experiments. [ABSTRACT FROM AUTHOR]

This paper presents an innovative driving method for a magnetically driven microtool to achieve precise positioning control while maintaining a high power output derived from commercialized permanent magnets. An effective driving methodology using permanent magnets, whose axes are parallel to driving direction, is applied to reduce friction force on the microtool. The positioning accuracy improves by five times and the response speed becomes ten times faster against the driving stage than in the conventional method. Furthermore, this method has been extended to two-degree-of-freedom movements, and the performance of the magnetically driven microtools is experimentally validated by oocyte manipulation. [ABSTRACT FROM AUTHOR]

Commercial magnetic recording media employ magnetic-field-induced two different magnetization states ±M to write data. In this paper, we present a magnetic memory cell in which electric-field-induced two different coercive-field Hc states (i.e., low-Hc and high-Hc) rather than ±M are served as writing data bits. A multiferroic magnetoelectric bilayer with Fe0.93Ge0.07 film grown on fully poled ferroelectric BiScO3-PbTiO3 substrate, exhibiting a large electric-field modulation of Hc, is used for illustration of such a prototype electric-write/magnetic-read memory cell which is nonvolatile. The reading process of the different coercive-field Hc information written by electric fields is demonstrated by using magnetoresistance read head. [ABSTRACT FROM AUTHOR]

In this paper, we study FePt/NM/FePt//MgO (NM=Pt or Pd) spin valves with perpendicular magnetization deposited by molecular beam epitaxy. Using extraordinary Hall effect and magnetoresistance, we show that the electrodes can be of different coercivities and magnetically decoupled, with current-in-plane magnetoresistances up to 0.8% at room temperature. Finally, using magnetic force microscopy observations, we prove that the different coercivities of the electrodes are controlled by different magnetization reversals and domain-wall pinning, thus allowing the obtaining of an antiparallel state. [ABSTRACT FROM AUTHOR]

This paper reports on a unique approach to influence the hydrogen desorption and recombination reaction in hydrogen disproportionated SmCo-type alloys upon heating in vacuum (HDDR process) by applying magnetic fields up to 4.1 T. The recombination reaction is affected strongly by the magnetic field. More specifically, hydrogen desorption is shifted to higher temperatures when the field is increased. This influence of magnetic field on the equilibrium of the HDDR reaction is qualitatively explained by its effect on the respective phase stability. It is related to the contribution of the magnetic energy term to the total Gibbs free energy of the reactants. [ABSTRACT FROM AUTHOR]

We have detected two typing errors in Fig. 2 of the published paper.1 The direct magnetoelectric (ME) measurements were carried out by sweeping magnetic fields of "100 Oe/s" for Fig. 2(a) and "5 Oe/s" for Figs. 2(b) and 2(c). The direct ME coefficient (αH) and the electric polarization (P) published in the paper were calculated from these correct sweep rates. Therefore, these errors do not alter the results and the discussions of our paper. [ABSTRACT FROM AUTHOR]

This paper predicts the possibility to achieve synchronization (via injection locking to a microwave current) of spin-transfer torque oscillators based on hybrid spin-valves composed by two free layers and two perpendicular polarizers at zero bias field. The locking regions are attained for microwave frequency near 0.5f0, f0, and 2f0, where f0 is the input oscillator frequency. Those properties make this system promising for applications, such as high-speed frequency dividers and multipliers, and phase-locked-loop demodulators. [ABSTRACT FROM AUTHOR]

Superconducting bulks can be magnetized to act as powerful permanent magnets; however, for high trapped fields at temperatures below 77 K, bulks have poor thermal stability and are limited by low mechanical strength. The trapped fields reported in this paper are between two stacks of commercial high-temperature superconducting tape each with 120 layers, magnetized by field cooling. 7.34 T was trapped at approximately 4.2 K, the highest field ever achieved for such a sample. The trapped field also continued to increase below 20 K showing high thermal stability, largely due to the silver over-layer which effectively dissipates heat. [ABSTRACT FROM AUTHOR]

In this paper, we show that Landau-Lifshitz-Bloch-Slonczewski equation can be envisaged as one of the best options for the modeling of heat assisted spin transfer torque writing. The model is tested on a Joule assisted switching problem for a macrospin under a polarized current, with all the values for the parameters in the typical range used technologically. The switching diagram in the presence of the current is presented, explained, and the agreement with published experimental data is discussed. [ABSTRACT FROM AUTHOR]