Nd<sub>2</sub>Fe<sub>14</sub>B domain structure imaged with MOKE
Fig. 1 MOKE image of the fractal domain pattern of Nd2Fe14B taken in the group of our collaborator Prof. Ruslan Prozorov.

The rare-earth magnetic alloy Nd2Fe14B is one of the strongest known permanent magnets and is widely used in industrial and commercial applications. In the thermally demagnetized state, Nd2Fe14B magnets display a high degree of fine-scale (~25nm) magnetic texture [1-2] and branched fractal-like domains [3-4] along the c-axis, that make them of interest for magnetic microelectromechanical applications (`Mag-MEMS'). This material has been studied in the past using magnetic force microscopy (MFM) [1,2,4,5], scanning electron microscopy (SEM) [5], and magneto-optic Kerr effect (MOKE) microscopy [3,4,6]. Our magnetic force microscope has additional cababilities that enable us to study the magnetic domains at smaller length-scales and lower temepratures than previous studies. Furthermore, we employ harder magnetic tips which we hope to use for domain manipulation.

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