Exciton Lifetime in PbS Quantum Dots in Glass
نویسندگان
چکیده
We report experimental measurements and analysis of HOMO-LUMO transition photoluminescence and photoinduced bleaching magnitude and decay kinetics in lead sulfide quantum dots in glass. We find that the radiative lifetime is independent of temperature from 77K to 500K. The lifetime of the HOMO-LUMO state decreases dramatically for T>300K, indicating thermally activated nonradiative recombination. The excitation decay time is much greater than the radiative lifetime and increases monotonically with decreasing temperature with decay times of 2 μs at room temperature and 4-10 μs at 77K.
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