Ion beam-induced luminescence and photoluminescence of 100 MeV Si8+ ion irradiated kyanite single crystals

Ionoluminescence (IL) of kyanite single crystals during 100 MeV Si8+ ion irradiation has been studied in the fluence range 1.87–7.50×1011 ions/cm2. Photoluminescence (PL) of similar dimensional crystals was recorded with same ions and energy in the fluence range 1×1011–5×1013 ions/cm2 with an excitation of 442 nm He–Cd laser beam. A sharp IL and broad PL peaks at ∼689 and 706 nm were recorded. This is attributed to luminescence centers activated by Fe2+ and Fe3+ ions. It is observed that up to a given fluence, the IL and PL peak intensities increase with increase of Si8+ ion fluence. The stability of the chemical species was studied on with and without irradiated samples by means of FT-IR spectroscopy. The results confirm that the O–Si–H type bonds covering on the surface of the sample. This layer might be acting as a protective layer and thereby reducing the number of non-radiative recombination centers.