A search for luminescence of the trivalent manganese ion in solid aluminates

Abstract

As an alternative way of examining the prospects of the trivalent manganese ion as a luminescent centre in glasses, Al2O3:Mn, ZnAl2O4:Mn and LaAlO3:Mn were investigated by means of spectrofluorometry. The luminescent species identified were divalent and tetravalent manganese and impurities (chromium), whereas trivalent manganese did not show luminescence at wavelengths ≤ 800 nm in LaAlO3:Mn and ZnAl2O4:Mn and ≤ 1000 nm in Al2O3:Mn for T down to liquid helium temperature. It is argued that both a strong crystal field and a large Jahn-Teller splitting quench the luminescence of trivalent manganese and these results lower the benefits for using this ion in glasses.