Magnetism in Natural Interfaces—Direct Observations by Electron Holography—

Yasukazu Murakami^a,b, Koudai Niitsu^c, Toshiaki Tanigaki^d, Hyun Soon Park^e, Ryosuke Kainuma^f, Daisuke Shindo^g,c

^a Department of Applied Quantum Physics and Nuclear Engineering, Kyushu University
^bThe Ultramicroscopy Research Center, Kyushu University
^cCenter for Emergent Matter Science, RIKEN
^dResearch & Development Group, Hitachi Ltd.
^eDepartment of Materials Science and Engineering, Dong-A University
^fDepartment of Materials Science, Tohoku University
^gInstitute of Multidisciplinary Research for Advanced Materials, Tohoku University

Abstract: An interface is a structural imperfection that significantly affects magnetic and electric properties in crystalline solids. Studies of the interface magnetism are vitally important for technologies related with permanent magnets, magnetic recording, magnetoelectronics, etc. However, it remains yet challenging to reveal the magnetism in natural interfaces, such as antiphase boundaries (APBs) in ordered alloys, because of the complex shape and the extremely small thickness. This paper reports on the electron holography study that determined magnetic flux density from narrow APBs produced in an ordered alloy, Fe₇₀Al₃₀.

Key words: electron holography, antiphase boundary, magnetic flux density, degree of atomic ordering, magnetic domain structure