Modification of photoluminescence wavelength and decay constant of Cr:Gd3Ga5O12 substituted by Ca/Si cation pair

In this study, the photoluminescence wavelength and decay constant of Cr:Gd3Ga5O12 garnet oxide were modified by substituting Gd3+/Ga3+ cations with a Ca2+/Si4+ cation pair. The primary objective of this study was to shift the emission wavelength to the near-infrared (NIR) region and accelerate decay of Cr:Gd3Ga5O12 for its potential use as a scintillation detector in medical applications. The incorporation of Ca2+ and Si4+ ions in site of Gd3+/Ga3+ ions resulted in a significant redshift in the photoluminescence wavelength of Cr3+ ions and an acceleration of decay. The results clearly demonstrated that Ca2+/Si4+ cation pair substitution is a clearly effective strategy for modulating the optical properties of Cr:Gd3Ga5O12, with the potential to develop a NIR garnet scintillator.