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.

Microscope scheme

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