Real-time scanning hall probe microscopy

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1996-08-26
Oral, Ahmet
HENİNİ, M
We describe a low-noise scanning Hall probe microscope having unprecedented magnetic field sensitivity (similar to 2.9x10(-8) T/root Hz at 77 K), high spatial resolution, (similar to 0.85 mu m),nd operating in real-time (similar to 1 frame/s) for studying flux profiles at surfaces. A submicron Hall probe manufactured in a GaAs/A1GaAs two-dimensional electron gas (2DEG) is scanned over the sample to measure the surface magnetic fields using conventional scanning tunneling microscopy positioning techniques. Flux penetration into a high T-c YBa2Cu3O7-delta thin film has been observed in real time at 85 K with single vortex resolution. Flux is seen to enter the film in the form of vortex bundles as well as single flux quanta, Phi(0). (C) 1996 American Institute of Physics.
APPLIED PHYSICS LETTERS

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Citation Formats
A. Oral and M. HENİNİ, “Real-time scanning hall probe microscopy,” APPLIED PHYSICS LETTERS, pp. 1324–1326, 1996, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/38181.