The effect of temperature on the triboluminescence of Ba, Sr, Ca and Pb doped NaCl and LiF single crystals
B P Chandra; M S K Khokhar; M Elyas; S M D Rao; B P Chandra; Dept. of Postgraduate Studies & Res. in Phys., Rani Durgavati Univ., Jabalpur, India; M S K Khokhar; Dept. of Postgraduate Studies & Res. in Phys., Rani Durgavati Univ., Jabalpur, India; M Elyas; Dept. of Postgraduate Studies & Res. in Phys., Rani Durgavati Univ., Jabalpur, India; S M D Rao; Dept. of Postgraduate Studies & Res. in Phys., Rani Durgavati Univ., Jabalpur, India
Журнал:
Journal of Physics D: Applied Physics
Дата:
1990-01-14
Аннотация:
The triboluminescence (TL) intensity of unirradiated Ba, Sr, Ca and Pb doped NaCl and LiF single crystals decreases with temperature and disappears completely at 105+or-5 and 180+or-10 degrees C respectively. The temperature T<sub>c</sub> at which TL disappears changes slightly with increasing concentration of the dopants. The temperature dependence of total TL intensity follows the relation I<sub>T</sub>=I<sub>T</sub><sup>0</sup>(1-T/T<sub>c</sub>)<sup>n</sup>, where I<sub>T</sub><sup>0</sup> is a constant and n lies between 0.5 and 0.6 for the unirradiated divalent impurity doped NaCl and LiF crystals. It is concluded that the decrease in the TL intensity with temperature may be primarily due to the decrease in charge density of the newly created surfaces. The increase in TL intensity with increasing dopant concentration is attributed to the increasing hardness of the crystals.
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