Pressure-induced amorphization in gadolinium scandium gallium garnet by x-ray diffraction and spectroscopic studies

Abstract

We report the first example of amorphization of garnets at high pressure and ambient temperature. Synchrotron x-ray diffraction and fluorescence spectroscopy at high pressure were performed on polycrystalline gadolinium scandium gallium garnet (GSGG) doped with and . X-ray diffraction measurements reveal a loss of long-range order beginning at GPa. This is followed by a change in local environment for dopants at 70 GPa as indicated by the loss of fluorescence emission. The amorphous phase is retained at ambient conditions, after decompression. We present possible mechanisms for these two distinct transformations in GSGG.