The influence of transition metal ions Ru, Co and Co combination with Al on the light-induced and holographic properties of Bi12SiO20 (BSO) crystals is studied. A significant enhancement of the response time is detected at 633 nm when the crystals are simultaneously exposed with green light, i.e. by optical excitation energy close to the location of the main photorefractive center in sillenite structure. Furthermore, prolonged read-out process is detected in Ru-doped BSO, probably due to the Ru ability to exist in three valence states simultaneously, among which some may appear only after appropriate illumination. A possibility to control the electron-hole competition in BSO: Co + Al crystal, due to the charge compensation, is demonstrated. A theoretical model is proposed to explain the complicated holographic behavior.
|Number of pages||16|
|Journal||Optical Memory and Neural Networks (Information Optics)|
|State||Published - 1 Mar 2011|