0000000000428586
AUTHOR
Marek Berkowski
Pressure-induced amorphization of the Y3Ga5O12 garnet studied to 1 Mbar
We use micro-beam synchrotron x-ray diffraction to study the pressure-induced amorphization of nano-sized and single crystals of Y3Ga5O12 up to pressures exceeding 1 Mbar in static compression. The abrupt pressure-induced amorphization found for both 56 nm and bulk micrometric crystals at around 76 GPa independently of the pressure transmitting medium employed demonstrates its intrinsic nature, previously predicted at 79 GPa by ab initio calculations. The single crystal structural solution at 50 GPa shows that the contraction of the unit-cell, mostly accommodated by the compressible YO8 dodecahedra, gives rise to a regularization and tilting increase of the GaO6 polyhedra with the Y?O-Ga an…
Band Gap Engineering and Trap Depths of Intrinsic Point Defects in RAlO3 (R = Y, La, Gd, Yb, Lu) Perovskites
The work was supported by the Polish National Science Centre (Project No. 2018/31/B/ST8/00774), by the NATO SPS Project G5647, and by the Ministry of Education and Science of Ukraine (Project DB/Kinetyka no. 0119U002249). L.V. acknowledges support of the National Research Foundation of Ukraine under Grant No. 2020.02/0373 “Crystalline phosphors’ engineering for biomedical applications, energy saving lighting and contactless thermometry”. Researchers from Tartu were supported by the ERDF fundings in Estonia granted to the Centre of Excellence TK141 “Advanced materials and high-technology devices for sustainable energetics, sensorics and nanoelectronics (HiTechDevices)” (Grant No. 2014-2020.4…
Dielectric and magnetic properties of CdMoO4:Gd3+ single crystal
Broadband dielectric spectroscopy and magnetic measurements provide experimental evidence that the CdMoO4:Gd 3+ single crystal is the paramagnet with low relative dielectric permittivity (er � 8), which slightly depends on the temperature and frequencies. Magnetization with zero coercivity and remanence is almost a universal function of l0H/T, characterizing superparamagnetic-like behavior. These results are being considered in a framework of the random distribution of the Ga 3+ ions in the tetragonal structure.