Optical Spectroscopy of Pentavalent Chromium Ions in Glass

In this work, the authors report the first spectroscopic observation of octahedrally coordinated pentavalent chromium ions in BaCaMg aluminate glasses. A broad band emission peaking at 780 nm with band width of 3,000 cm{sup {minus}1} has been observed at 12 K. The measurements of fluorescence decay, time-resolved emission and excitation spectra reveal that the emission band is an overlapped luminescence originating from both the {sup 2}E to {sup 2}T{sub 2} transition of octahedrally coordinated Cr{sup 5+} and a charge transfer transition of Cr{sup 6+}O{sub 4} groups. This study is important for laser physics.