Changes in trap parameters in various mixed oxide garnets

• Thermally stimulated luminescence of mixed oxide garnet ceramics was studied.
• TSL of Cr-, Yb-related impurity defects was identified in many garnet compositions.
• Table of Cr-related trap positions in energy gap for mixed garnets was created.
• Cr-related trap was found at 0.4–1.4 eV bellow the CB, depending on garnet composition.

Shallow and deep electronic traps in various mixed oxide garnet ceramics (Y,Lu,Gd)3(Al,Ga)5O12 have been studied by thermally stimulated luminescence spectroscopy in the 80–550 K temperature range. It is shown that the substitution of Al ions by Ga and Y by Gd or Lu in YAG:Ce affects the properties of the traps. It is established that the studied ceramics contain residual impurities of chromium and ytterbium. On the base of the obtained and literature data, a table of the Cr-related trap position relative to the bottom of the conduction band in RE3(Gax,Al5-x)5O12:Ce garnets (RE = Lu, Y, Gd and combinations thereof) has been constructed.