Gd3Ga5O12 (GGG), which crystallizes in the garnet structure at ambient conditions, was observed to transform to a high-pressure phase at 88 GPa after laser heating at 1500 K. This new phase is stable at least up to 180 GPa, and can be preserved on decompression to 50 GPa. This phase is cubic and consistent with a perovskite structure of stoichiometry (Gd0.75Ga0.25)GaO3. The zero-pressure bulk modulus, K0, obtained from fitting to a Birch-Murnaghan equation of state is 373(5) GPa with a fixed pressure derivative K0′=4. At 170 GPa, the bulk modulus of perovskite-type GGG is 979(15) GPa, which is comparable to that of diamond at the same pressure [956(21) GPa] and consistent with recently reported shock-compression data for Gd3Ga5O12. The new high-pressure phase of Gd3Ga5O12 is thus highly incompressible.
|Original language||English (US)|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - Feb 24 2011|
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics