Luminescence in anion-defective α-Al_2O_3 crystals over the nano-, micro- and millisecond intervals

摘要

Optical absorption, thermoluminescence (TL), and stationary and time-resolved spectra of X-ray luminescence (XL) and cathodic luminescence (CL) in anion-defective α-Al_2O_3 crystals have been studied. It was found that the XL and CL spectra were dominated by the luminescence of F~+-centers over the nanosecond interval, Al_i~+- and Ti~(3+)-centers over the microsecond interval, and F- and Cr~(3+)-centers over the millisecond interval of the relaxation time. It was shown that the luminescence of F~+-centers made the decisive contribution to the released energy at the first stage of relaxation. The CL light sum illuminated in the F-band correlated with the TL yield in radiation detectors based on α-Al_2O_3.