2017/07/09 by Fikáček Jan, Jan, Fikáček, Vít Kopecký +7
Engineering · Materials Science · #FOS: Physical sciences #Magnetic Properties and Applications #Magnetic and transport properties of perovskites and related materials #Materials Science (cond-mat.mtrl-sci) #Metallic Glasses and Amorphous Alloys #Shape Memory Alloy Transformations
paper · pdf · doi:10.48550/arxiv.1707.02619
openalex publication_date 2017/07/09 · openalex created_date 2022/09/28 · openalex updated_date 2026/07/28
We carried out magneto-optical Kerr effect (MOKE) and magnetization\nmeasurements on a single crystal of Ni2.00Mn1.16Ga0.84 in a longitudinal\ngeometry. While there had been reports of polar geometry measurements so far,\nwe show that - against earlier predictions - surface magnetic states of the\nmartensite and the austenite can be also probed efficiently via longitudinal\nMOKE. A single variant magnetic state, which occurs at room temperature, is\ncharacterized by ferromagnetic hysteresis loops similar to standard\nferromagnets. Temperature dependencies of Kerr rotation were found to be\nlinearly proportional to magnetization for martensitic phases. After passing\nthrough an inter martensitic structural transition at around 260 K in zero\nmagnetic field, the coercive fields are more than doubled in comparison with\nthe room temperature values. On the other hand, at higher temperatures above\n338 K where an austenite structure is formed, the MOKE signals are dominated by\nquadratic contributions and the magnitude of Kerr rotation drops due to changes\nin the electronic and magnetic domains structure. After the sample is cooled\nacross the austenite-martensite transition again, we observed a multiple beam\nreflected by the sample due to different types of structural domains present on\nits surface.\n