Luminescence from self-trapped holes in manganese-doped calcium fluoride single crystals


Thermally stimulated luminescence (TSL) and electron spin resonance (ESR) measurements on X-irradiated CaF2:Mn (0.1 wt.%) single crystals have been conducted in the interval 70 to 300 K. Prominent TSL peaks occur near 150 K (345- and 495-nm emission) and 200 K (predominanlty 495-nm emission) with thermal decay of ESR centers at these same temperatures. Taken collectively the data suggest that 150 K TSL emission is due to mobile holes from VK centers recombining with both trapped electrons and Mn+ ions, i.e., VK + e- → 345-nm emission, and VK + Mn+ → (Mn2+)* + hv (495-nm emission). Additionally, H centers are formed by transformation of VK centers. At 200 K, holes from H centers recombine with Mn+ to produce excited-state (Mn2+)* which decays by emitting 495-nm radiation. © 1988.

Publication Title

Journal of Luminescence