Magnetic phases of a highly frustrated magnet, ZnCr2O4, up to an ultra-high magnetic field of 600 T

The Faraday rotation and magneto-optical absorption spectral measurements were conducted to reveal the full-magnetization process and map out a magnetic phase diagram of a typical geometrical frustrated magnet, ZnCr2O4, by using the electromagnetic flux compression method in ultra-magnetic fields up to 600 T. A fully polarized ferromagnetic phase is observed in which the absorption spectra associated with an exciton-magnon-phonon transition disappears. Furthermore, prior to the fully polarized ferromagnetic phase above 410 T, we found a novel magnetic phase above 350 T followed by a canted 3:1 phase.