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Abstract

Irradiation effects of 8 MeV electrons on photoluminescence properties of thioglycolic acid (TGA) capped CdTe quantum Dots (QD) are presented. Steady-state and time-resolved photoluminescence (PL) spectroscopy were used for anlayzing PL properties of both irradiated and unirradiated quantum dots. The Photoluminescence peak, intensity and lifetimes were found to vary with dose. At lower doses (up to 5kGy), they were found increasing and at higher doses (up to 20kGy) it decreased. The PL peak position also shifted toward low energy and broadened with increase of dose. Initial increase in PL intensity (upto 5kGy) is due to passivation of surface defects leading to high radiative recombination. At higher doses the damage of capping layer takes place leading to aggregation effects.

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