Local magnetism in permalloy patterns by focused magneto-optic Kerr effect

Abstract

Abstract:

An investigation on the local magnetization processes within patterned permalloy films is performed by means of focused magneto-optic Kerr effect (MOKE) measurements, from which local magnetic hysteresis loops of the individual elements are found to be dependent on the shape and separation between the individuals as well as the position in the array. For the rectangular elements, the easy magnetization axis is along the length of element and the hard axis is along width of element. The shape anisotroy increases with increasing the length to width aspect ratio. When the separation between elements is larger than the element size, positions of elements in the array is relatively less influential on the behaviour of the magnetic hysteresis loops which are just the contribution of an individual element. When the separation between elements is close to the element size, the magnetic anisotropy shown in the magnetic Kerr loops is affected by the element position indicating that the magnetic interaction should be taken into account.

Key words: laser physics, magnetic anisotropy, focused magneto-optic Kerr effect, patterned film, chemical wet etching

CLC Number:

O469

SUN Li, HAN Qi, ZHAO Chong-yi, HUANG Zhao-cong, ZHAI Ya， XU Yong-bing. Local magnetism in permalloy patterns by focused magneto-optic Kerr effect[J]. J4, 2015, 32(4): 492-497.

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