X-ray Exited Optical Luminescence of Eu in Diamond Crystals Synthesized at High-pressure High-temperature

Abstract

Diamond powders with inclusions of europium atoms were synthesized at high pressure (7.7 GPa) and temperature (1800oC) from a mixture of pentaerythritol, C(CH2OH)4, and pyrolyzate of diphthalocyanine (C64H32N16Eu) served as a special precursor. In prepared diamonds by X-ray fluorescence spectroscopy, we have found the concentration of Eu atoms of 51±5 ppm that is by two orders of magnitude greater than that in known natural and synthetic diamonds. X-ray diffraction, SEM, X-ray exited optical luminescence, Raman and IR spectroscopy have confirmed the formation of diamond monocrystals of high quality with em-bedded Eu atoms and a nitrogen content of ~500 ppm. Numerical simulation has allowed us de-termine the energy cost of 5.8 eV needed for the incorporation of a single Eu atom with adjacent vacancy into growing diamond crystal (528 carbons).