Cr3+: SrGa12O19: A Broadband Near-Infrared Long-Persistent Phosphor

Cr3+-doped SrGa12O19 is demonstrated to be a broadband near-infrared (650-950nm) long-persistent phosphor whose luminescence can last for more than 2h after ultraviolet irradiation is stopped. Detailed analysis of the photoluminescence and thermoluminescence spectra and of the persistent decay behavior of the Cr3+-doped SrGa12O19 samples indicate that the persistent energy transfer from the SrGa12O19 host to the Cr3+ ions and the filling and release of electrons into and from the shallow and deep traps through the conduction band is responsible for the long-persistent phosphorescence.