Investigating the Super Paramagnetic Limits of Ferromagnetic Nanowires

Authors

  • C. V. Ezeh Federal University Oye Ekiti, Ekiti state Nigeria
  • J. C. Ehiabhili
  • D. A. Allwood

DOI:

https://doi.org/10.24203/ajas.v7i4.5848

Keywords:

Permalloy, nanowires, coercivity, superparamagnetic transition

Abstract

Highly sensitive focused magneto optical Kerr effect magnetometer (MOKE) has been used to explore the nanoscale limit of state of the art electron beam lithography (EBL) patterned permalloy (NiFe) nanowires. The nanowires are 20 µm long arranged in 20 µm × 20 µm arrays. Permalloy of different thicknesses, which includes 10, 8, 6, 4 and 3.5 nm were deposited on 5 different samples containing these arrays. Results from 10 nm thick permalloy nanowires shows superparamagnetic transition at 85 ± 5 nm wire width. For 6 nm thick array, superparamagnetic transition occurs at 125 ± 25 nm. We therefore show that with 10 nm thickness, instead of 6 nm thickness, more miniaturisation of nanowire width can be achieved before the onset of superparamagnetism. This may be seen as very efficient in achieving increased storage density in memory devices.

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Published

2019-08-24

How to Cite

Ezeh, C. V., Ehiabhili, J. C., & Allwood, D. A. (2019). Investigating the Super Paramagnetic Limits of Ferromagnetic Nanowires. Asian Journal of Applied Sciences, 7(4). https://doi.org/10.24203/ajas.v7i4.5848

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Section

Articles