Top-loading He-3 Cryostat and Variable Temperature Insert

May 2012

Janis Research Company is proud to announce the development of a top-loading He-3 cryostat with sample in He-3 liquid, as well as a variable temperature insert with sample in He-4 vapor. These cryostats were designed to fit a 32mm room temperature bore magnet at the National High Magnetic Field Laboratory (NHMFL) in Tallahassee, Florida, with a maximum sample space of 17mm.

NHMFL scientists have used these cryostats to study the Fermi surface of alpha-Uranium via quantum oscillations. The shape of the Fermi surface can be reconstructed by measuring the deHaas-vanAlphen oscillations in the magnetization as the field is swept over the sample. These oscillations were measured as a function of angle of the applied field and temperature. Measuring the temperature dependence of the oscillations can determine the effective masses of the electrons, which is a measure of the level of interaction the electrons have with each other and the crystal lattice.