Magnetometry

The magnetic property setup is part of a cryogen-free measurement system at variable temperature and magnetic fields. It allows the measurement of magnetic moment through two seamlessly interchangeable modules: a low frequency vibrating magnetometer (VSM) and AC susceptibility. A heated sample platform, compatible with both measurement modules, is also available to extend the temperature range up to 700K.

The Cryogenic VSM module is a tool for the measurement of DC magnetic moments. In order to generate a signal proportional to the magnetic moment, the sample is set to vibrate in a constant (or slowly varying) applied field. The signal is detected by a static pair of pick-up coils. The coils sense the variation of magnetic flux due to the sample movement. The pick-up coils are located inside a top-loading insert loaded into the Variable Temperature Insert (VTI) within the bore of the superconducting magnet. The signal is detected by a lock-in amplifier.

The AC magnetic susceptibility module performs measurements by applying a small AC field using a drive (or primary) field coil and detecting the sample response with a static pair of pick-up (or secondary) coils. The sample can be top loaded manually into the coil set. The system uses phase sensitive detection operating over a wide frequency range.