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The electric field is an energy‐efficient tool that can be leveraged to control spin–orbit coupling. Although Dzyaloshinskii–Moriya interactions (DMI) in magnetic skyrmion systems can be regulated in flat state using an electric field, the control of their flexible behavior has remained elusive so far. Here, the double modulation of strain and voltage effects in a flexible ultrathin heavy metal (HM)/ferromagnetic (FM)/insulator (I) system, demonstrating that the interfacial DMI can be dual controlled via a mechanical stress and a circuit gating voltage at room temperature, is reported. An intensive tuning efficiency (26.7 mJ m−2 V−1) is obtained while maintaining an excellent mechanical strength, which is a result of Rashba‐DMI tuning at the FM/I interface. The result is promising in achieving novel flexible topological devices where low operation voltage and excellent flexibility are required. [ABSTRACT FROM AUTHOR]

Measurement of magnetic signal from an arbitrary direction is of vital importance for applications in magnetic navigation, space science, indoor positioning, and magnetic gesture recognition. However, magnetoresistive sensors, as vector magnetometers, are only suitable for detection of magnetic signals along the magnetic hard axis. Magnetoelectric coupling is introduced to control the magnetic anisotropy of a magnetoresistive pattern, realizing a 90° rotation of the magnetic hard axis and thus the sensing direction of the tunable sensor. The sensitivity along the initial magnetic easy axis can be enhanced 12.7‐fold while that along the initial hard axis can be depressed to be only 4.7% of the original value through magnetic anisotropy engineering. The tailorable directional sensitivity of the electric‐field reconfigurable sensor speaks to the strong potential of this system for practical applications requiring testing of localized magnetic fields, for example, magnetic diagnosis or biomagnetic characterization. [ABSTRACT FROM AUTHOR]

The inexorable trend of next generation spintronics is to develop smaller, lighter, faster, and more energy efficient devices. Ultimately, spintronics driven by free energy, for example, solar power, is imperative. Here, a prototype photovoltaic spintronic device with an optical‐magneto‐electric tricoupled photovoltaic/magnetic thin film heterojunction, where magnetism can be manipulated directly by sunlight via interfacial effect, is proposed. The magnetic anisotropy is reduced evidenced by the out‐of‐plane ferromagnetic resonance (FMR) field change of 640.26 Oe under 150 mW cm−2 illumination via in situ electron spin resonance (ESR) method. The transient absorption analysis and the first‐principles calculation reveal that the photovoltaic electrons doping in the cobalt film alter the band filling of this ferromagnetic film. The findings provide a new path of electron doping control magnetism and demonstrate an optical‐magnetic dual controllable logical switch with limited energy supply, which may further transform the landscape of spintronics research. [ABSTRACT FROM AUTHOR]

Interfacial magnetism between an yttrium iron garnet (YIG) and copper layer has been modulated by an ionic liquid gating method, which causes a large ferromagnetic resonance shift of YIG, as reported by Bin Peng, Ziyao Zhou, Ming Liu, and co‐workers in article number 1805592. This finding opens a door toward compact, high‐performance, and energy‐efficient spintronic devices. [ABSTRACT FROM AUTHOR]

Ferromagnetic insulator thin film nanostructures are becoming the key component of the state‐of‐the‐art spintronic devices, for instance, yttrium iron garnet (YIG) with low damping, high Curie temperature, and high resistivity is explored into many spin–orbit interactions related spintronic devices. Voltage modulation of YIG, with great practical/theoretical significance, thus can be widely applied in various YIG‐based spintronics effects. Nevertheless, to manipulate ferromagnetism of YIG through electric field (E‐field), instead of current, in an energy efficient manner is essentially challenging. Here, a YIG/Cu/Pt layered nanostructure with a weak spin–orbit coupling interaction is fabricated, and then the interfacial magnetism of the Cu and YIG is modified via ionic liquid gating method significantly. A record‐high E‐field‐induced ferromagnetic resonance field shift of 1400 Oe is achieved in YIG (17 nm)/Cu (5 nm)/Pt (3 nm)/ionic liquid/Au capacitor layered nanostructures with a small voltage bias of 4.5 V. The giant magnetoelectric tunability comes from voltage‐induced extra ferromagnetic ordering in Cu layer, confirmed by the first‐principle calculation. This E‐field modulation of interfacial magnetism between light metal and magnetic isolator may open a door toward compact, high‐performance, and energy‐efficient spintronic devices. A record‐high E‐field‐induced ferromagnetic resonance field shift of 1400 Oe is achieved in an yttrium iron garnet/Cu/Pt/ionic liquid/Au capacitor heterostructure with a small voltage bias of 4.5 V characterized via in situ electron spin resonance spectroscopy. The giant magnetoelectric tunability comes from voltage‐induced extra ferromagnetic ordering in the Cu layer, confirmed by the first‐principle calculation. [ABSTRACT FROM AUTHOR]

Voltage control magnetism is one of the most energy efficient pathway towards magnetoelectric (ME) device. Ionic liquid gating (ILG) method has already shown impressive manipulation power at the IL/electrode interface to influence the structure, orbital as well as spin of the electrode materials. As key material in anisotropy magnetoresistance sensor and spin valve heterostructure, the permalloy Ni 0.81 Fe 0.19 was utilized as the electrode to investigate the ILG induced magnetic anisotropy change. In this work, we realized magnetic anisotropy control in Au/[DEME]+[TFSI]-/Ni 0.81 Fe 0.19 (2.5 nm)/Ta heterostructure via ILG caused electrostatic doping. This is evidenced in situ reversible ferromagnetic field (H r) shift with electron spin resonance (ESR) spectrometer. Aiming at the question whether the charge accumulation at the ionic liquid interface is the main control mechanism at low voltage, we carefully tested the relationship between the change of resonance field and the amount of surface charge. It was found that these two had a good linear relationship between −1 V and +1 V. Defining the linear parameter as A whose value is 28.7 mT m2/Col. Unlike previously reported chemical regulation of Co, this article used ionic liquids to physically regulate NiFe, which has not been studied in the previous ionic liquid regulation. And NiFe has a narrower resonance line width for easy reference to microwave devices. In addition, It also has a stronger ferromagnetic signal than Co, which can be more easily detected as a sensor device. Therefore, this system is more promising. The ILG control NiFe may lead to a new kind of magnetoelectric sensor devices and path a new way to low energy consumption spintronics. • We demonstrate the feasibility of low voltage (1 V) regulation of magnetic anisotropy. • A linear relationship between the surface charge density and the resonance field offset was observed and the linear coefficient was calculated to be 28.7 mT m2/Col. [ABSTRACT FROM AUTHOR]

[Display omitted] • The single-orientation flexible La 0.7 Sr 0.3 MnO 3 thin film was prepared. • A reversible magnetoelectric coefficient of 50 Oe/V was obtained. • The tunability of the flexible structures was not damaged by deformation. The flexible La 0.7 Sr 0.3 MnO 3 (LSMO) film shows good mechanical stretchability and property stability under bending states, which makes it a candidate material for flexible electronics and spintronics devices. Here the microwave magnetism of flexible LSMO thin film has been manipulated effectively by the ionic gel (IG) gating process. A reversible and non-volatile magnetoelectric (ME) coefficient of 50 Oe/V was observed using electron paramagnetic resonance (ESR) technology at the flat multilayer structure. This ME coupling is caused by the electrons hopping between Mn3+ and Mn4+ ions under the interfacial electric double layer. When the membranes were bent to a radius of curvature of 15 mm, a larger ME coefficient of 67 Oe/V was also observed, which indicating that this flexible structure can work effectively under mechanical deformation. This work demonstrates the voltage control of magnetism for flexible correlated materials and paves a way towards wearable low-power devices based on flexible manganite films. [ABSTRACT FROM AUTHOR]