The most hard-working piece of our equipment is a magneto-optical microscope initially installed by Anatolii Polyanskii. It allows visualization of magnetic flux distribution with
- spatial resolution 1 micron,
- field resolution 1 Gauss
- temporal resolution 10 ms.
This magneto-optical microscope was the first one to resolve individual Abrikosov vortices carrying one flux quantum, see Single-Vortex Magneto-Optics.
The physical idea behind the magneto-optical imaging is the Faraday effect (1846), i.e., the field-induced rotation of the light polarization. Below you can see a rough sketch of the technique, and illustration of the Faraday effect, and double Faraday rotation.
A lot of magneto-optical images and other magneto-optical information can be found on Magneto-Optical Imaging of Superconductors page.