Photoluminescence upconversion in colloidal CdTe quantum dots
نویسندگان
چکیده
Efficient photoluminescence ~PL! up-conversion has been observed in colloidal CdTe quantum dots with an energy gain of as high as 360 meV. Compared with the normal PL, the peak energy of this up-converted PL ~UCPL! shows a redshift of about 80 meV, and the corresponding radiative lifetime becomes nearly twice as long. This UCPL is attributed to the carrier recombination involving surface states mainly through a thermal excitation process.
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