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Through a systematic investigation of the magnetization rotation and reversal in an exchange‐biased NiFe/MnIr film electrically detected by spin rectification effect (SRE), we experimentally demonstrate that this SRE DC voltage can be detected in the field‐swept spectra both at resonant and nonresonant conditions. The spectra show clear shifted hysteretic curves driven by exchange bias and a hysteresis loop is formed at applied magnetic field around exchanged bias field by the nonzero SRE DC voltage with sign change with the sweeping direction. More interestingly, we found that the voltage magnitude changes upon switching of magnetization can be greatly enhanced at resonance thereby suggesting an attractive approach to realize a highly sensitive method to measure exchange bias field. This experimental behavior can be interpreted within the framework of the near‐resonant spin rectification effect. [ABSTRACT FROM AUTHOR]

The present work describes the fabrication of yttrium iron garnet (YIG) nanofibers prepared via electrospinning method. The YIG nanofibers with diameters of around 80 nm were formed when calcinations temperature exceeded 750 °C. The morphology and magnetic parameters including saturation magnetization ( M s ) and coercivity ( H c ) of these samples dramatically change with variation of the annealing temperature. In particular, the M s displays a steady increase from 3.1 emu/g at 700–21.5 emu/g at 1000 °C, and the H c shows a different tendency that first increases to a maximum value of 140 Oe at 750 °C, and then reduce distinctly. Finally, the electron spin resonance spectra display strong asymmetry and broad linewidth that are highly affected by shape anisotropy, defects and the presence of trace amount second phase orthorhombic YFeO 3 ( o -YFeO 3 ) in the YIG nanofibers. [ABSTRACT FROM AUTHOR]

Cobalt ferrite (CoFeO) nanoribbons with high crystallinity and purity were synthesized by annealing the as-spun PVP/[Co(NO)+Fe(NO)] precursor nanoribbons at temperatures from 450 to 750 °C in air, and they were certified to have an improved coercivity ( H) and considerable saturation magnetization ( M). Although all the prepared CoFeO nanoribbons presented an excellent ferromagnetism behavior at room temperature, their M progressively increased with increasing annealing temperature but H followed an opposite variation tendency. The maximum M of about 80.3 emu g of the nanoribbons annealed at 750 °C was basically equal to the bulk value, and the maximum H of about 1802 Oe of the nanoribbons annealed at 450 °C, is larger than most of reported H values of other one-dimensional CoFeO nanostructures by far. It suggested that the magnetization reverse processes of the CoFeO nanoribbons annealed at 450 and 550 °C were dominated by the coherent rotation model, while that of the CoFeO nanoribbons annealed at 650 and 750 °C were dominated by the growth of a reverse magnetic domain. [ABSTRACT FROM AUTHOR]

Highlights • Film with stripe domain and good properties were fond of bcc and bcc + fcc phases. • Acoustic and optical modes were changed by the microwave field and stripe domain. • Acoustic and optical modes showed good resonance in bcc and bcc + fcc phases. Abstract FeNi films with different phase structures were prepared by electrodeposition method, and the phase structure of the film was controlled by the composition of the film. The results indicated that the well-defined stripe domain patterns and good magnetic properties of the films were fond of the bcc and bcc + fcc phase structures of the FeNi films. The results of permeability spectra indicated that the acoustic and optical modes of the film could be changed by the direction of the microwave field and stripe domain. FeNi stripe domain films exhibited the different frequency under the two modes, and the acoustic and optical modes of film showed obvious spectra in the bcc and bcc + fcc phases of FeNi films. The results are helpful to the development of the stripe domain optical mode microwave devices. [ABSTRACT FROM AUTHOR]

• Electrodeposited and sputtered FeNi stripe domain films were systematic studied. • The rotation of stripe domain is lagging behind magnetization reversal. • Stripe domain emerges dynamic hysteresis before saturation field. • Magnetization dynamics of stripe domain were dependent on stripe direction. • Different resonance modes are determined by local magnetization. FeNi films with the stripe domain (SD) pattern are prepared by electrodeposition and sputtering methods. The magnetic domain, static magnetic parameters, and quality factor, as well as dynamic properties of the two films, are respectively performed. The results show the magnetizations of the film were dependent on the direction of SD, and the rotation of the SD is lagging behind the magnetization reversal. The microwave properties of the SD emerge dynamic hysteresis before the saturation magnetic field. These microwave properties are selectively excited with acoustic mode, optical mode, and spin-wave mode. The frequency and intensity of different resonance modes of stripe domain are determined by the local magnetization. The magnetization variations and the rotation of SD of different modes are further illuminated by the micromagnetic simulation. The magnetic anisotropy and the resonance intensity of permeability of different modes were finally described by the modified resonance equations. [ABSTRACT FROM AUTHOR]