Fega

Acoustically actuated magnetoelectric (ME) antennas utilize acoustic wave resonance to complete the process of receiving and transmitting signals, which promotes the development of antenna miniaturization technology. This paper presents a bilayer magnetostrictive/AlN ME laminated antenna. The proposed laminated antenna uses the FeGa/FeGaB bilayer materials as magnetostrictive materials, which combine the advantages of soft magnetic properties of FeGa and the low loss of FeGaB. First, multiphysics modeling and analysis are performed for the proposed ME laminated antenna by finite element method (FEM)...

With the progressive aging of the population, bone fractures are an increasing major health concern. Diverse strategies are being studied to reduce the recovery times using nonaggressive treatments. Electrical stimulation (either endogenous or externally applied electric pulses) has been found to be effective in accelerating bone cell proliferation and differentiation. However, the direct insertion of electrodes into tissues can cause undesirable inflammation or infection reactions. As an alternative, magnetoelectric heterostructures (wherein magnetic fields are applied to induce electric polarization) could be used to achieve electric stimulation without the need for implanted electrodes...

Optomechanical magnetometers enable highly sensitive magnetic field sensing. However, all such magnetometers to date have been optically excited and read-out either via free space or a tapered optical fiber. This limits their scalability and integrability, and ultimately their range of applications. Here, we present an optomechanical magnetometer that is excited and read-out via a suspended optical waveguide fabricated on the same silicon chip as the magnetometer. Moreover, we demonstrate that thermomechanical noise limited sensitivity is possible using portable electronics and laser...

A co-sputtering process for the deposition of Fe0.8 Ga0.2 B alloy magnetostrictive thin films is studied in this paper. The soft magnetic performance of Fe0.8 Ga0.2 B thin films is modulated by the direct-current (DC) sputtering power of an FeGa target and the radio-frequency (RF) sputtering power of a B target. Characterization results show that the prepared Fe0.8 Ga0.2 B films are amorphous with uniform thickness and low coercivity. With increasing FeGa DC sputtering power, coercivity raises, resulting from the enhancement of magnetism and grain growth...

Iron impurities are believed to act as deep acceptors that can compensate for the n-type conductivity in as-grown Ga2 O3 , but several scientific issues, such as the site occupation of the Fe heteroatom and the complexes of Fe-doped β-Ga2 O3 with native defects, are still lacking. In this paper, based on first-principle density functional theory calculations with the generalized gradient approximation approach, the controversy regarding the preferential Fe incorporation on the Ga site in the β-Ga2 O3 crystal has been addressed, and our result demonstrates that Fe dopant is energetically favored on the octahedrally coordinated Ga site...

For the first time, a comprehensive analytical method based on a one-dimensional metal-organic framework comprising "quick, easy, cheap, effective, rugged, and safe-dispersive micro solid phase extraction-dispersive liquid-liquid microextraction" was introduced in this research. Moreover, the first-ever attempt was accomplished to apply the iron-gallic acid metal-organic framework in analytical method development. The goal of the research was to analyze the pesticide content of watermelon comprehensively in its flesh and juice...

A magnetically tunable magnetoelectric transducer consisting of rectangular Fe82 Ga18 (FeGa)/Pb(Zr,Ti)O3 (PZT) composites is developed, and their magnetoimpedance and magnetocapacitance effects are investigated under bending and longitudinal modes. Specifically, the composites' impedance and capacitance are found to vary with dc magnetic field Hdc , which results from the varied effective dielectric permittivity of the FeGa/PZT composite with Hdc due to the delta E effect, magnetostrictive effect of FeGa and mechanism responsible for ME coupling between the FeGa and PZT layers...

Osteosarcoma is a malignant bone cancer that usually occurs in children and adolescents. Although chemotherapy, radiotherapy and other methods have been used to treat osteosarcoma, these therapeutic regimens fail to cure this disease completely. Herein, doxorubicin-encapsulated iron-gallic acid (FeGA-DOX) nanoparticles (NPs) were fused with agarose hydrogels (AG) for synergistic therapy of osteosarcoma. Under near-infrared laser irradiation, the local temperature of FeGA-DOX NPs was increased. Therefore, tumour cells were killed using photothermal therapy, and AG dissolved to release FeGA-DOX into the cells...

Flexible materials have brought up a new era of application-based research in stretchable electronics and wearable devices in the last decade. Tuning of magnetic properties by changing the curvature of devices has significant impact in the new generation of sensor-based technologies. In this work, magnetostrictive FeGa thin films have been deposited on a flexible Kapton sheet to exploit the magneto-elastic coupling effect and modify the magnetic properties of the sample. The FeGa alloy has high magnetostriction constant and high tensile strength making its properties susceptible to external stress...

Chemodynamic therapy (CDT) is an effective anti-tumor method, while CDT alone cannot achieve a good therapeutic effect. Moreover, the overexpression of glutathione (GSH) in tumor cells dramatically limits the efficiency of CDT. Here, we proposed a hydrogel co-loading SO2 prodrug and FeGA nanoparticles (NPs) for enhancing CDT by photothermal-triggered SO2 gas therapy (FBH) system by mixing benzothiazolyl sulfonates (BTS) and FeGA NPs in a certain ratio and encapsulating them in a heat-sensitive hydrogel. FeGA NPs could accelerate the release of Fe2+ under acidic conditions and light, and combine with excess H2 O2 in the tumor for chemokinetic treatment...

Due to its responsiveness to the tumour microenvironment (TME), chemodynamic therapy (CDT) based on the Fenton reaction to produce cytotoxic reactive oxygen species (ROS) to destroy tumor has drawn more interest. However, the Fenton's reaction potential for therapeutic use is constrained by its modest efficacy. Here, we develop a novel injectable hydrogel system (FMH) on the basis of FeGA/MoS2 dual quantum dots (QDs), which uses near-infrared (NIR) laser in order to trigger the synergistic catalysis and photothermal effect of FeGA/MoS2 for improving the efficiency of the Fenton reaction...

The strain-driven interfacial coupling between the ferromagnetic and ferroelectric constituents of magnetoelectric (ME) composites makes them potential candidates for novel multifunctional devices. ME composites in the form of thin-film heterostructures show promising applications in miniaturized ME devices. This article reports the recent advancement in ME thin-film devices, such as highly sensitive magnetic field sensors, ME antennas, integrated tunable ME inductors, and ME band-pass filters, is discussed...

Higher doses of radiotherapy (RT) are associated with resistance induction, therefore highly selective and controllable radiosensitizers are urgently needed. To address this issue, we developed a FeGA-based injectable hydrogel system (FH) that can be used in combination with low-dose radiation. Our FH can deliver FeGA directly to the tumor site via intratumoral injection, where it is a reservoir-based system to conserve FeGA. The photothermal properties of FeGA steadily dissolve FH under laser irradiation, and, simultaneously, FeGA reacts with a large amount of H2 O2 in the cell to produce OH (Fenton reaction) which is highly toxic to mitochondria, rendering the cell inactive and reducing radiotherapy resistance...

The potential use of electrodeposition to synthesize a hybrid magnetostrictive/magnetoelectric layered system is shown in this paper. By appropriately adjusting pH, growth potential, and electrolyte composition, it is possible to achieve thin films in which magnetoelectric oxide GaFeO3 (GFO) is formed in close contact with magnetostrictive metallic FeGa alloy. X-ray diffractometry shows the formation of FeGa as well as GFO and Fe oxides. Electron microscopy observations reveal that GFO mainly segregates in grain boundaries...

Hydroxyl radical (•OH)-mediated chemodynamic therapy (CDT) is an emerging antitumor strategy, however, acid deficiency in the tumor microenvironment (TME) hampers its efficacy. In this study, a new injectable hydrogel was developed as an acid-enhanced CDT system (AES) for improving tumor therapy. The AES contains iron-gallic acid nanoparticles (FeGA) and α-cyano-4-hydroxycinnamic acid (α-CHCA). FeGA converts near-infrared laser into heat, which results in agarose degradation and consequent α-CHCA release...

The energy spectrum of positronium atoms generated at a solid surface reflects the electron density of states (DOS) associated solely with the first surface layer. Using spin-polarized positrons, the spin-dependent surface DOS can be studied. For this purpose, we have developed a spin-polarized positronium time-of-flight spectroscopy apparatus based on a ^{22}Na positron source and an electrostatic beam transportation system, which enables the sampling of topmost surface electrons around the Γ point and near the Fermi level...

Co2 Fe0.4 Mn0.6 Si (CFMS) and Co2 FeGa0.5 Ge0.5 (CFGG) Heusler alloys are among the most promising thin film materials for spintronic devices due to a high spin polarization, low magnetic damping and giant/tunneling magnetoresistance ratios. Despite numerous investigations of Heusler alloys magnetic properties performed up to now, magnetoelastic effects in these materials remain not fully understood; due to quite rare studies of correlations between magnetoelastic and other magnetic properties, such as magnetic dissipation or magnetic anisotropy...

Multiferroic heterostructures based on the strain-mediated mechanism present ultralow heat dissipation and large magnetoelectric coupling coefficient, two conditions that require endless improvement for the design of fast nonvolatile random access memories with reduced power consumption. This work shows that a structure consisting of a [Pb(Mg1/3 Nb2/3 )O3 ]0.7 -[PbTiO3 ]0.3 (001) substrate on which a crystalline FeGa(001)/MgO(001) bilayer is deposited exhibits a giant magnetoelectric coupling coefficient of order 15 × 10-6 s m-1 at room temperature...

Magnetic composites of soft magnetic FeGa particles embedded in a silicone matrix have been synthesized. The Villari effect has been studied depending on the size and concentration of the particles and on the magnetic state of the composite. The results indicate a decrease in the Villari effect when the concentration of the magnetic particles increases. These results suggest a relationship between the Villari effect and the mechanical properties of the composites. The Young's modulus of the composites has been obtained by microindentation and their values related to the intensity and slope of the Villari signals...

Here we report the possibility of creating synthetic domain walls in nominal [Fe72 Ga28 /Tb33 Fe67 ]2 multilayers. The magnetization as a function of the temperature reveals the absence of Compensation temperature in the samples which can be understood considering an interdiffusion process that results in the formation of TbFeGa alloys at the nominal FeGa layers. Therefore, samples actually comprise TbFeGa and TbFe layers. The hysteresis loops exhibit magnetization steps related to the nucleation of domain walls formed because of the competition between different interactions: (i) the antiferromagnetic exchange coupling between the heavy rare earth (Tb) and the transition magnetic metal (Fe) inside each layer, (ii) the antiferromagnetic coupling between Tb and Fe at the interfaces, and (iii) the Zeeman energy...