Using Kerr microscopy for direct observation of magnetic domains in Ni–Mn–Ga magnetic shape memory alloy

0481168 - FZÚ 2018 RIV US eng J - Journal Article
Heczko, Oleg - Perevertov, Oleksiy - Král, D. - Veis, M. - Soldatov, I.V. - Schäfer, R.
Using Kerr microscopy for direct observation of magnetic domains in Ni–Mn–Ga magnetic shape memory alloy.
IEEE Transactions on Magnetics. Roč. 53, č. 11 (2017), s. 1-5, č. článku 2502605. ISSN 0018-9464. E-ISSN 1941-0069
R&D Projects: GA ČR GA16-00043S; GA ČR GA15-00262S
Institutional support: RVO:68378271
Keywords : ferroelastic domains * Kerr magneto-optical microscopy * magnetic domain structure * martensite
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 1.467, year: 2017

Giant magnetic-field-induced strain up to 12% in Ni–Mn–Ga single crystal is due to magnetically-induced reorientation of the twinned martensitic low symmetry crystal structure. An important interplay is arising from the interaction between ferroelastic domains (twin domains) and magnetic domains. Here, we studied the magnetic domains in an Ni50Mn28Ga22 single crystal exhibiting 6% strain by using a magneto-optical indicator film and for the first time also directly by the Kerr magneto-optical microscopy. To compare the magnetization behavior of bulk and surface, we measured the magnetization loops by the Kerr effect (MOKE) and by the vibrating sample magnetometry. We demonstrate that using a particular arrangement of the Kerr microscopy enables visualizing the magnetic domains structure and its evolution in the magnetic field.
Permanent Link: http://hdl.handle.net/11104/0276772