VUV excitation of luminescence in pure and Tl+ doped KI

Excitation spectra of pure and Tl⁺ doped KI have been measured at room temperature (RT) and liquid nitrogen temperature (LNT) between 13 and 30 eV. Energy transfer between the host lattice ions and the Tl⁺ impurities, and intrinsic recombinaton of electron-hole pairs, have been studied at different temperatures and excitation energies. Energy transfer has been observed only at RT while at LNT the intrinsic recombination, V_k centers-electrons, is the dominant process.