Near-infrared luminescence of OH− and Cl− doped Bi4Ge3O12 crystals

OH− and Cl− doped Bi4Ge3O12 (BGO) single crystals had been grown by Vertical Bridgman (VB) method. The structure of these crystals was determined by XRD, the transmittance and emission spectra in near infrared region (NIR) were measured at room temperature. 5% OH− doped BGO shows a significant emission band peaking around 1181 nm under 808 nm laser diodes (LDs) excitation, and the 5% Cl− doped BGO exhibits a relatively weak emission band as well. 100% and 5% OH− doped BGO show noticeable emission band centered at about 1346 nm under 980 nm LDs excitation.

► 5% OH− doped BGO shows emission at 1181 nm under 808 nm LDs excitation.
► 100% and 5% OH− doped BGO shows emission at 1346 nm under 980 nm LDs excitation.
► The emission might be ascribed to the lower valence Bi ions (Bi2+ and/or Bi+).