Spectral Properties of Barium Fluoride Crystals Colored by Electronic Injection Using a Pointed Anode

Barium fluoride(BaF2) crystals were colored by electric injection using a pointed anode with a homemade electric injec-tion apparatus at various temperatures and voltages.The current versus time relationship during the electric injection was determined.The absorption spectra of electric injection colored BaF2 crystals at room temperature were analyzed.The results show that the mas-sive F color centers are produced in the colored crystals.According to the electric injection coloration mechanism,the F color centers could not be produced by using a pointed anode.By using measured current-time curves,we could explain the mechanism of F color center formation for the electric injection colored crystals.In the electric injection coloration process,V color centers inside the crys-tal were initially produced near the anode,and then the F color centers were transformed from the V color centers absorbed photons.