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Flexible electronic devices extended abilities of humans to perceive their environment conveniently and comfortably. Among them, flexible magnetic field sensors are crucial to detect changes in the external magnetic field. State‐of‐the‐art flexible magnetoelectronics do not exhibit low detection limit and large working range simultaneously, which limits their application potential. Herein, a flexible magnetic field sensor possessing a low detection limit of 22 nT and wide sensing range from 22 nT up to 400 mT is reported. With the detection range of seven orders of magnitude in magnetic field sensor constitutes at least one order of magnitude improvement over current flexible magnetic field sensor technologies. The sensor is designed as a cantilever beam structure accommodating a flexible permanent magnetic composite and an amorphous magnetic wire enabling sensitivity to low magnetic fields. To detect high fields, the anisotropy of the giant magnetoimpedance effect of amorphous magnetic wires to the magnetic field direction is explored. Benefiting from mechanical flexibility of sensor and its broad detection range, its application potential for smart wearables targeting geomagnetic navigation, touchless interactivity, rehabilitation appliances, and safety interfaces providing warnings of exposure to high magnetic fields are explored. [ABSTRACT FROM AUTHOR]

Layered perovskite-like oxides with the Aurivillius phase's structure are promising for high-technology industries such as magnetoelectronics, photonics, and catalysis. This work reports the synthesis condition and magnetic properties of the Sr-doped ceramic materials (BSFTO) based on four-layer Aurivillius phase Bi5FeTi3O15. (Bi1−xSrx)5FeTi3O15−δ (x = 0–0.14) ceramics were synthesized by a solid-state reaction method, and their structure (XRD), morphology (SEM, helium pycnometry), elemental composition (EDX), and sintering (dilatometry) were investigated. The XRD/EDX measurements show that the single-phase materials based on BSFTO solid solutions were synthesized with x = 0.0–0.1, which corresponds to the content of strontium 0–50 mol.%. The optimal synthesis regimes of the obtained materials and their sintering temperatures were determined. At x < 0.1, field dependent magnetization indicates a possible low-temperature magnetic ordering, and they have nonzero magnetization at RT. The results of the present work confirm the possibility of successful synthesis of pure-phase BSFTO materials that can have promising functional applications. [ABSTRACT FROM AUTHOR]

Materials with a layered perovskite-like structure of the Aurivillius phase type are important for technology fields such as magnetoelectronics and photocatalysis. Features of phase formation during the synthesis of nano- and macrocrystalline materials based on Bi6Fe2Ti3O18 with the five-layer Aurivillius phase structure are described. Samples were characterized by powder XRD, DSC/TG, dilatometry, and SEM/EDX. The temperatures of the beginning of formation, the Curie point, the beginning of decomposition and activation of sintering of the obtained materials, and the value of the coefficient of linear thermal expansion were determined. The technological possibility of controlling the dispersion of the obtained materials by changing the synthesis conditions is shown. [ABSTRACT FROM AUTHOR]

Based on magneto‐electric (ME) effect and spin Hall effect (SHE), the authors propose a novel spin logic device named MESH‐SLD. In MESH‐SLD, the charge current is transmitted in the channel by employing inverse SHE, which solves the dissipation problem of spin current in the channel of all‐spin logic device (ASLD). By using a magnetization‐dynamics/spin‐transport hybrid model, the authors have investigated the influence of working voltage, channel lengths, and materials on the performance of the MESH‐SLD. And the simulation results show that the energy dissipation of the MESH‐SLD only increases approximately linearly with the increase of channel length, while the switching delay remains almost unchanged. In addition, with the increase of the spin Hall angle of the channel material, the energy dissipation and the minimum working voltage of the MESH‐SLD decrease significantly. Most importantly, compared with conventional ASLD, the proposed MESH‐SLD improve the switching delay and the energy dissipation by about 2.5 times and 851.8 times, respectively. [ABSTRACT FROM AUTHOR]

With the merits of high sensitivity, high stability, high flexibility, low cost, and simple manufacturing, flexible magnetic field sensors have potential applications in various fields such as geomagnetosensitive E-Skins, magnetoelectric compass, and non-contact interactive platforms. Based on the principles of various magnetic field sensors, this paper introduces the research progress of flexible magnetic field sensors, including the preparation, performance, related applications, etc. In addition, the prospects of flexible magnetic field sensors and their challenges are presented. [ABSTRACT FROM AUTHOR]

Abstract Based on magneto‐electric (ME) effect and spin Hall effect (SHE), the authors propose a novel spin logic device named MESH‐SLD. In MESH‐SLD, the charge current is transmitted in the channel by employing inverse SHE, which solves the dissipation problem of spin current in the channel of all‐spin logic device (ASLD). By using a magnetization‐dynamics/spin‐transport hybrid model, the authors have investigated the influence of working voltage, channel lengths, and materials on the performance of the MESH‐SLD. And the simulation results show that the energy dissipation of the MESH‐SLD only increases approximately linearly with the increase of channel length, while the switching delay remains almost unchanged. In addition, with the increase of the spin Hall angle of the channel material, the energy dissipation and the minimum working voltage of the MESH‐SLD decrease significantly. Most importantly, compared with conventional ASLD, the proposed MESH‐SLD improve the switching delay and the energy dissipation by about 2.5 times and 851.8 times, respectively.

Till now application of printed magnetoelectronics is hindered by lack of large area exchange coupled metallic multilayers required to produce printable magneto‐sensory inks. Large‐scale roll‐to‐roll (R2R) fabrication process is an attractive approach owing to its capabilities for high volume, high throughput, and large area manufacturing. Precise and high performance R2R sputtering technology is developed to fabricate large area giant magnetoresistive (GMR) thin‐films stacks that contain 30 metallic bilayers prepared by continuous R2R sputtering of Co and Cu sequential on a hundred meters long polyethylene terephthalate (PET) web. The R2R sputtered Co/Cu multilayer on a 0.2 × 100 m2 PET web exhibits a GMR ratio of ≈40% achieving the largest area exchange coupled room temperature magneto‐sensitive system demonstrated to date. The prepared GMR thin‐film is converted to magnetosensitive ink that enables printing of magnetic sensors with high performance in a cost‐efficient way, which promotes integration with printed electronics. An average GMR ratio of ≈18% is obtained for 370 printed magnetic sensors. The realized precise R2R sputtering approach can also be extended to a wide range of hybrid thin‐film material systems opening up a path for new functional inks applied with printing technologies. [ABSTRACT FROM AUTHOR]

Active magnetic motion sensing relies on a combination of magnetic sensors and actuators to indirectly sense a time-varying change in position and orientation. Based on our previous work on a 1D setup with magnetoelectric (ME) sensors, we introduce a concept for a full 6D sensing system, which is positioned as a modular setup for human movement pattern capture with regard to neurodegenerative diseases. In this paper, we implemented an inverse model based on ideal triaxial sensors and coils. We then included results from the previous experiments to estimate the prospective performance in a physical setup. We obtained a spatial error of a few cm and approx. 10° with focus on superimposed sinusoidal movements of 1, 5, and 10 Hz. [ABSTRACT FROM AUTHOR]

With the merits of high sensitivity, high stability, high flexibility, low cost, and simple manufacturing, flexible magnetic field sensors have potential applications in various fields such as geomagnetosensitive E-Skins, magnetoelectric compass, and non-contact interactive platforms. Based on the principles of various magnetic field sensors, this paper introduces the research progress of flexible magnetic field sensors, including the preparation, performance, related applications, etc. In addition, the prospects of flexible magnetic field sensors and their challenges are presented.

Crack difficulties are important research topics for multiferroic composite media, which offer a lot of potential for producing multifunctional devices. It is put into consideration the magneto-electro-thermo-elastic coupling effect. The two crack surfaces are symmetrically loaded by a combination of homogeneous thermal, magnetic, electric, and mechanical loadings. Only the shallower region of a deep flaw in the wall structure inside the skin-depth layer impacts the initial temperature Induction Thermography (IT) response while assessing ferromagnetic constructions, but the deeper part has zero influence. This paper provides an exhaustive overview of these crack behavior studies as well as proposes a course of action for future exploration. Based on the literature, three types of crack behavior, which are magnetoelastic, ferromagnetic, and piezoelectric (PE), were explored significantly. Literature reviews have indicated that the magnetoelastic crack studied is popular among researchers around the world. Besides, the procedure and conditions are easier and faster compared to ferromagnetic and PE. Future research should therefore concentrate on the investigation effects of the magnetoelastic crack. [ABSTRACT FROM AUTHOR]

The dynamic response of an anisotropic multilayer magneto-electro-elastic (MEE) plate due to an external excitation is investigated in this work, using the stiffness matrix approach. A parametric study is performed by varying the stacking sequence, polarization direction, boundary conditions, and interlayer thickness. The proposed method yields the numerical estimation of the dispersion curve and the free vibration of the Lamb waves for different crystallographic orientations and magneto-electric boundary conditions. It is demonstrated that the anisotropy highly affects the dispersion curve and the non-dimensional frequency, and also decreases the interlayer thickness of the magneto-electro-elastic multilayer and raises the phase velocity of the fundamental symmetric Lamb mode vibration. The key outcomes of this research can serve as a reference in the design and analysis of new smart magneto-electro-elastic structures. [ABSTRACT FROM AUTHOR]

We have examined a dynamical spin injection in a CoFeB/Pt/CoFeB trilayered structure. Although the contribution of the spin pumping was eliminated by the symmetric spin injection from the upper and lower CoFeB layers, a clear voltage change due to the inverse spin Hall effect has been observed. We find that the observed signal can be quantitatively explained by considering the thermal spin injection due to the heating effect during ferromagnetic resonance (FMR). This innovative demonstration indicates the significant contribution of FMR heating in the dynamical spin injection. [ABSTRACT FROM AUTHOR]

Stretchable strain sensors that can be attached to the human body to respond to various strains and convert mechanical stimuli into readable digital signals have attracted immense attention. High sensitivity and excellent mechanical properties are required to capture subtle strains while retaining high stretchability and stability. Composite structural engineering, involving the geometric design and local assembly layout of macroscopic structures, the design and alignment-direction adjustment of microstructures, and the reasonable combination thereof, is an effective strategy for improving the sensing performance of strain sensors and achieving multifunctional integration. Composite structural engineering is broadly divided into natural inspiration and artificial intervention. The present discussion begins from the perspective of composite structural design of active materials and elastic substrates, and selected engineering cases are subsequently described in the order of progressively increasing dimensions. The underlying mechanisms of composite structural engineering are related with change in the Young's modulus or sectional area of substrates, achieving macro-/micro-structural design and high alignment of active materials, and exploiting synergistic effects. Multifunctional integrated devices developed by interdisciplinary intersection, involving mechanical metamaterials, mechanochromic materials, magnetoelectronics, and energy and sensory systems, are summarized. Finally, novel applications, future challenges, and the outlook of stretchable strain sensors are discussed. [Display omitted] [ABSTRACT FROM AUTHOR]

Traditionally, the primary field, where curvature has been at the heart of research, is the theory of general relativity. In recent studies, however, the impact of curvilinear geometry enters various disciplines, ranging from solid-state physics over soft-matter physics, chemistry, and biology to mathematics, giving rise to a plethora of emerging domains such as curvilinear nematics, curvilinear studies of cell biology, curvilinear semiconductors, superfluidity, optics, 2D van der Waals materials, plasmonics, magnetism, and superconductivity. Here, the state of the art is summarized and prospects for future research in curvilinear solid-state systems exhibiting such fundamental cooperative phenomena as ferromagnetism, antiferromagnetism, and superconductivity are outlined. Highlighting the recent developments and current challenges in theory, fabrication, and characterization of curvilinear micro- and nanostructures, special attention is paid to perspective research directions entailing new physics and to their strong application potential. Overall, the perspective is aimed at crossing the boundaries between the magnetism and superconductivity communities and drawing attention to the conceptual aspects of how extension of structures into the third dimension and curvilinear geometry can modify existing and aid launching novel functionalities. In addition, the perspective should stimulate the development and dissemination of research and development oriented techniques to facilitate rapid transitions from laboratory demonstrations to industry-ready prototypes and eventual products., (© 2021 The Authors. Advanced Materials published by Wiley-VCH GmbH.)