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Abstract
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The pure and Eu2?-doped NaCl crystal were successfully grown by the melt
(Czochralski) method. The structural, mechanical and optical properties were
characterized by carrying out X-ray diffraction (XRD), micro-hardness, optical
absorption, photoluminescence (PL) and thermoluminescence (TL) measurements.
The XRD analysis indicates that the Eu2+ ions have been incorporated
into the NaCl crystal matrix and the diffraction peak shifts toward lower 2h
angle. Hardness measurement has shown a decrease of crystal hardness with
indentation load. Optical absorption spectrum has shown the presence of peaks
at 211, 224, 231, 255, 320 and 352 nm. Results of PL analysis indicate that the
emission peak exists the characteristic peak of bivalent Eu ions corresponding to
the t2g(4f65d) -8S7/2(4f7) transition. The TL glow curve of NaCl:Eu2+ crystal
has shown two peaks located at 108.6 and 199.6 C with different trap depth, the
intensity of the high-temperature peak is found to be larger than the low-temperature
one.
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