Scanning Hall Probe Microscopy
Scanning Hall Probe Microscope
We developed a low-noise Scanning Hall Probe Microscope with unprecedented magnetic field sensitivity of ~2.9×10-8 T/Sqrt(Hz) at 77K, high spatial resolution of ~0.2 - 0.8 µm, scan range 25µm×25µm at 77 K, operating in real-time (~1 frame/s) for studying flux profiles.
A submicron Hall probe manufactured in a GaAs/AlGaAs two dimensional electron gas (2DEG) is scanned over the sample to measure the surface magnetic fields using conventional scanning tunneling microscopy positioning techniques.
The microscope is placed in a cryostat containing a 1.5-300K variable temperature insert and a 7T superconducting magnet. The cryostat is mounted on a double stage vibration isolation system to eliminate external disturbances. Microscope can measure a conventional STM image, an image of the perpendicular component of the magnetic field and these two profiles simultaneously.
Image of Vortices in a thin film of YBCO
Hexagonal Lattice of Flux lines in a BSCCO single crystal
Vortices pinned by a Regular Array of Magnetic Dots
SHPM with STM tracking or a Ferrite-Garnet Film
Test MFM structure