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The well‐known ferromagnetic oxide, NiFe2O4, was studied as a potential candidate for room‐temperature Type II magnetoelectrics. A spin canting as one of the essential requirements for Type II multiferroics was induced by breaking the stoichiometry, that is, intentionally subtracting Fe ions. We observed that Fe ions were first subtracted exclusively from the tetrahedral sites, leading to an increase in the magnetoelectric coupling owing to an increasing degree of spin canting. The enhancement in the magnetoelectric coupling culminated beyond the subtraction level of ~30 at.%, at which Fe ions started to be removed from the octahedral sites. Alongside, we observed that the subtraction of Fe ions gives rise to a ferroelectricity due to the formation of defect complexes that establish an internal bias field. [ABSTRACT FROM AUTHOR]

An improved magnetic energy harvesting with magneto‐mechano‐electric (MME) generator is demonstrated by low‐loss piezoelectric single‐crystal fibers composite to realize a self‐powered electronics. The low‐loss MME generator can generate voltage of 94 Vpp and current of 120 μA (corresponding to an output root mean square power density of 2.1 mW cm−3). [ABSTRACT FROM AUTHOR]

This study demonstrates the modulation of off-resonance magnetoelectric ( ME) response of the Pb(Zr,Ti)O3 ( PZT)/ Metglas (Fe BSi) bilayered composite by laser annealing. A continuous-wave 532 nm Nd: YAG laser with varying fluences (210-390 J/mm2) was utilized to anneal the 2 μm thick PZT film deposited using granule spray in vacuum ( GSV) technique on magnetostrictive amorphous Metglas foil. It was found that the dielectric and ferroelectric properties of the PZT film are strongly affected by the exposure to laser fluence. The ME voltage coefficient of PZT/Metglas increased with the fluence up to 345 J/mm2, reaching a high value of 880 mV/cm·Oe. The electrical and ME properties were correlated with the changes observed in crystallinity and grain size of the PZT film as well as with the alterations in microstructure and magnetic behavior of Metglas. Our results demonstrate that enhanced ME coupling can be realized in PZT/Metglas film composites by controlling the laser fluence. [ABSTRACT FROM AUTHOR]

Dielectric capacitors, which store electrical energy in the form of an electrostatic field via dielectric polarization, are used in pulsed power electronics due to their high power density and ultrashort discharge time. In pursuit of developing high‐performance dielectric capacitors, special attention has been given to the improvement of their energy density and storage efficiency, which would make them useful for an even wider variety of applications. Among the different dielectric materials studied so far, including polymers, glasses, and both bulk and film‐based ceramics, dielectric ceramic films, which are of particular interest for miniature power electronics and mobile platforms, have demonstrated the greatest energy storage performances. In this regard, several interesting approaches involving physical, chemical, and microstructural modifications of the dielectric ceramic films are adopted. In addition to a brief discussion of the polymers, glasses, and ceramics used in dielectric capacitors and key parameters related to their energy storage performance, this review article presents a comprehensive overview of the numerous efforts made toward enhancing the energy storage properties of linear dielectric, paraelectric, ferroelectric, relaxor ferroelectric, and anti‐ferroelectric ceramic films for their applications in pulsed power capacitors. Dielectric capacitors, which store energy in the form of an electrostatic field and release it in an extremely short period of time to create intense power pulses, have applications in pulsed power electronics used in various commercial, civilian, and military systems. Significant progress has been made toward the development of dielectric ceramic film capacitors with high energy storage performance. [ABSTRACT FROM AUTHOR]