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Detecting quadrupole: a hidden source of magnetic anisotropy for Manganese alloys.

ABSTRACT: Mn-based alloys exhibit unique properties in the spintronics materials possessing perpendicular magnetic anisotropy (PMA) beyond the Fe and Co-based alloys. It is desired to figure out the quantum physics of PMA inherent to Mn-based alloys, which have never been reported. Here, the origin of PMA in ferrimagnetic Mn_{3- ?} Ga ordered alloys is investigated to resolve antiparallel-coupled Mn sites using x-ray magnetic circular and linear dichroism (XMCD/XMLD) and a first-principles calculation. We found that the contribution of orbital magnetic moments in PMA is small from XMCD and that the finite quadrupole-like orbital distortion through spin-flipped electron hopping is dominant from XMLD and theoretical calculations. These findings suggest that the spin-flipped orbital quadrupole formations originate from the PMA in Mn_{3- ?} Ga and bring the paradigm shift in the researches of PMA materials using x-ray magnetic spectroscopies.

SUBMITTER: Okabayashi J

PROVIDER: S-EPMC7297735 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Detecting quadrupole: a hidden source of magnetic anisotropy for Manganese alloys.

Okabayashi Jun J Miura Yoshio Y Kota Yohei Y Z Suzuki Kazuya K Sakuma Akimasa A Mizukami Shigemi S

Scientific reports 20200616 1

Mn-based alloys exhibit unique properties in the spintronics materials possessing perpendicular magnetic anisotropy (PMA) beyond the Fe and Co-based alloys. It is desired to figure out the quantum physics of PMA inherent to Mn-based alloys, which have never been reported. Here, the origin of PMA in ferrimagnetic Mn<sub>3- δ</sub> Ga ordered alloys is investigated to resolve antiparallel-coupled Mn sites using x-ray magnetic circular and linear dichroism (XMCD/XMLD) and a first-principles calcula ...[more]

PMID: 32546779

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