Changes in the optical absorption induced by sequential exposition to short- and long-wavelength radiation in the BTO:Al crystal

2016 International Conference on Defects in Insulating Materials

Shandarov, S.M.^1 ; Dyu, V.G.^1 ; Kisteneva, M.G.^1 ; Khudyakova, E.S.^1 ; Smirnov, S.V.^1 ; Akrestina, A.S.^1 ; Kargin, Yu F.^2

State University of Control System and Radioelectronics, Tomsk, Russia^1

A.A. Baikov Institute of Metallurgy and Materials Science RAS, Moscow, Russia^2

关键词: Impurity absorption;    Lattice relaxation;    Meta-stable state;    Photoinduced transition;    Reversible change;    Short wavelengths;    Spectral dependences;    Wavelength radiation;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/169/1/012005/pdf
DOI  :  10.1088/1757-899X/169/1/012005

来源: IOP

【 摘 要 】

Modifications of the spectral dependences of the optical absorption induced in the Bi12TiO20:Al crystal as a result of sequential exposition to cw laser radiation first with the wavelength λg= 532 nm and then with the longer wavelength λl,n= 588, 633, 655, 658, 663, 700, 780, 871, or 1064 nm are investigated. We revealed that after the short-wavelength exposition to radiation with λg= 532 nm, the optical absorption in the crystal increases, and in the range 470-1000 nm, yields the spectrum whose form is independent of a prehistory. The subsequent exposition to longer-wavelength radiation leads to bleaching of the crystal in the examined spectral range. A maximum diminishing of the optical absorption in the crystal is observed upon exposure to radiation with the wavelength λl,5= 663 nm. To describe the experimentally observed reversible changes in the optical absorption spectrum in the Bi12TiO20:Al we use the impurity absorption model that takes into account the photoinduced transitions between two metastable states of a deep defect center leading to the change of its position in the crystal lattice under conditions of strong lattice relaxation.