Unveiling the Mechanism for the Split Hysteresis Loop in Epitaxial Co2Fe1-xMnxAl Full-Heusler Alloy Films

Tao, X. D.; Wang, H. L.; Miao, B. F.; Sun, Lei; You, Bo; Wu, Di; Zhang, Weiyi; Oepen, Hans Peter; Zhao, Jianhua; Ding, Haifeng

doi:10.1038/srep18615

Cited by 7 publications

(2 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Here, upon decreasing the magnetic field from its saturation point, the particles may reorient while partially preserving their magnetic moment, thus leading to the observed split hysteresis where at a low field of ∼10 mT an inversion of the magnetic polarity is observed. Additionally, it has been shown that for magnetically anisotropic films the split hysteretic loop exists due to the reversal of magnetization at the edges of the film due to domain wall movement upon decreasing the field. − In our case, the SMBs possess magnetic anisotropy. Due to the presence of aligned MNPs in the SMBs, the edges of the particles may show a reversal of magnetization in demagnetizing field and such effect dominates near the switching fields (i.e., −10 to +10 mT).…”

Section: Resultsmentioning

confidence: 59%

Field-Driven Reversible Alignment and Gelation of Magneto-Responsive Soft Anisotropic Microbeads

2021

View full text Add to dashboard Cite

Magnetic fields offer untethered control over the assembly, dynamics, and reconfiguration of colloidal particles. However, synthesizing "soft" colloidal particles with switchable magnetic dipole moment remains a challenge, primarily due to strong coupling of the dipoles of the adjacent nanoparticles. In this article, we present a way to overcome this fundamental challenge based on a strategy to synthesize soft microbeads with tunable residual dipole moment. The microbeads are composed of a polydimethylsiloxane (PDMS) matrix with internally embedded magnetic nanoparticles (MNPs). The distribution and orientation of the MNPs within the PDMS bead matrix is controlled by an external magnetic field during the synthesis process, thus allowing for the preparation of anisotropic PDMS microbeads with internal magnetically aligned nanoparticle chains. We study and present the differences in magnetic interactions between microbeads containing magnetically aligned MNPs and microbeads with randomly distributed MNPs. The interparticle interactions in a suspension of microbeads with embedded aligned MNP chains result in the spontaneous formation of percolated networks due to residual magnetization. We proved the tunability of the structure by applying magnetization, demagnetization, and remagnetization cycles that evoke formation, breakup, and reformation of 2D percolated networks. The mechanical response of the microbead suspension was quantified by oscillatory rheology and correlated to the propensity for network formation by the magnetic microbeads. We also experimentally correlated the 2D alignment of the microbeads to the direction of earth's magnetic field. Overall, the results prove that the soft magnetic microbeads enable a rich variety of structures and can serve as an experimental toolbox for modeling interactions in dipolar systems leading to various percolated networks, novel magneto-rheological materials, and smart gels.

show abstract

Section: Resultsmentioning

confidence: 59%

Field-Driven Reversible Alignment and Gelation of Magneto-Responsive Soft Anisotropic Microbeads

2021

View full text Add to dashboard Cite

show abstract

“…One can see that, it decreases as x increases, revealing the lower frequency at Mnrich sample. This external field-dependent frequency mode was best determined by the dispersion of Kittel mode (or uniform precession mode) in the following, [26] taking the in-plane 097502-2 uniaxial and fourfold magnetic anisotropy effective fields H 2 and H 4 into consideration, and setting the external field H and magnetization M restricted in x-z plane for simplicity,…”

Section: Resultsmentioning

confidence: 99%

The unique magnetic damping enhancement in epitaxial Co₂Fe_1−xMn_xAl films*

Cheng

Meng

et al. 2019

Chinese Phys. B

View full text Add to dashboard Cite

Uniform precession dynamics and its magnetic damping are investigated in epitaxial Co2Fe1−x Mn x Al films by using the time-resolved magneto–optical Kerr effect under out-of-plane configuration. The decay time of uniform precession mode decreases, and thus the magnetic damping increases with the increase of external field. Moreover, the decay time decreases as x decreases, so that the enhancement of magnetic damping occurs in Fe-rich sample. Furthermore, the decay time decreases as the excitation fluence increases, which drops rapidly at low magnetic field comparing with the slow reduction at high magnetic field. This unique magnetic damping enhancement is attributed to the enhancement of homogeneous magnetization.

show abstract

Control of magnetic anisotropy in epitaxial Co2MnAl thin films through piezo-voltage-induced strain

Bao

Wang

Cao

et al. 2018

Journal of Applied Physics

View full text Add to dashboard Cite

The voltage-controlled magnetic anisotropy of various magnetic materials is an effective method to realize the electronic devices with low power consumption. Here, we investigated the magnetic properties in Co2MnAl/GaAs heterostructures controlled by piezo voltages-induced strain using the magneto-optical Kerr effect microscopy. The coexistence of the in-plane cubic and uniaxial magnetic anisotropies was observed in the initial state of Co2MnAl thin films. The magnetic anisotropy was manipulated effectively by the piezo voltages. The two-step magnetic hysteresis loop measured along the [1−10] direction was changed into a square loop when the piezo voltage was −30 V (compressed state). On the contrary, the loop of the [110] direction was changed into a two-step loop. The loops of [100] and [010] axes represented the hard axes and were almost unchanged with the piezo voltages. We found that the transformations of loops in [110] and [1−10] axes were manipulated by the piezo voltage induced additional uniaxial anisotropy. Finally, we demonstrated that the planar Hall resistance (RH) in the Hall device can be effectively controlled by the piezo voltages. Our study identified that the voltage controlled room temperature magnetic devices through strain engineering could have great potential for spintronic applications.

show abstract

Unveiling the Mechanism for the Split Hysteresis Loop in Epitaxial Co2Fe1-xMnxAl Full-Heusler Alloy Films

Cited by 7 publications

References 45 publications

Field-Driven Reversible Alignment and Gelation of Magneto-Responsive Soft Anisotropic Microbeads

Field-Driven Reversible Alignment and Gelation of Magneto-Responsive Soft Anisotropic Microbeads

The unique magnetic damping enhancement in epitaxial Co₂Fe_1−xMn_xAl films*

Control of magnetic anisotropy in epitaxial Co2MnAl thin films through piezo-voltage-induced strain

Contact Info

Product

Resources

About

Unveiling the Mechanism for the Split Hysteresis Loop in Epitaxial Co2Fe1-xMnxAl Full-Heusler Alloy Films

Cited by 7 publications

References 45 publications

Field-Driven Reversible Alignment and Gelation of Magneto-Responsive Soft Anisotropic Microbeads

Field-Driven Reversible Alignment and Gelation of Magneto-Responsive Soft Anisotropic Microbeads

The unique magnetic damping enhancement in epitaxial Co2Fe1−xMnxAl films*

Control of magnetic anisotropy in epitaxial Co2MnAl thin films through piezo-voltage-induced strain

Contact Info

Product

Resources

About

The unique magnetic damping enhancement in epitaxial Co₂Fe_1−xMn_xAl films*