Room temperature magnetic imaging of magnetic storage media and garnet epilayers in the presence of external magnetic fields using a sub-micron GaAs SHPM

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2000-09-15

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SANDHU, Adarsh
MASUDA, Hiroshi
Oral, Ahmet
Bending, Simon.J.

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A multipurpose room temperature scanning Hall probe microscope (RT-SHPM) system incorporating an ultra-high sensitive sub-micron GaAs Hall probe (active area of 0.8 0.8 mm2 ; room temperature Hall coefficient of 0.3 O/G) exhibiting extremely high magneticfield sensitivity (0.04G/pHz) was used for the direct, non-invasive and quantitative imaging of magnetic field fluctuations in very close proximity to the surfaces of thin film magnetic storage media, Bi substituted iron garnet epilayers and demagnetized Sr-ferrite permanent magnets placed in external magnetic fields. A scanning tunnelling microscope tip integrated adjacent to the Hall probe was used for precise vertical positioning of the probe. RT-SHPM images of 1.4 MB written floppy disks clearly showed well-defined magnetic transitions to coalesce into small island-like structures under external perpendicular fields greater than 1300 Oe. The RT-SHPM is demonstrated to be a versatile means of quantitatively monitoring micron-sized magnetic domain structures in the presence of external magnetic fields at room temperature

Subject Keywords

Scanning hall probe microscope, Magnetic fields, Molecular beam epitaxy, Magnetic materials, Hall effect sensor, Heterojunction semiconductor devices

URI

https://hdl.handle.net/11511/33189

DOI

https://doi.org/10.1016/s0022-0248(01)00925-3

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Department of Physics, Conference / Seminar

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Citation Formats

A. SANDHU, H. MASUDA, A. Oral, and S. J. Bending, “Room temperature magnetic imaging of magnetic storage media and garnet epilayers in the presence of external magnetic fields using a sub-micron GaAs SHPM,” 2000, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/33189.