A micro-calorimeter working at ultra-low temperature down to 75 mK and high magnetic field up to 17.5 T has been developed. A typical sample weight is as small as 100 μg. A magnetic phase diagram of magnon Bose-Einstein condensation (BEC) in Ba 3Cr 2O 8 is determined. The scaling index of the phase boundary is very close to that of the isotropic three dimensional BEC at low temperature, in spite of the existence of Dzyaloshinskii-Moriya (DM) interaction which is confirmed in the previous ESR measurement.
- Magnon BEC
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- Materials Science(all)
- Condensed Matter Physics