TY - JOUR
T1 - Temperature Dependence of Excitonic and Biexcitonic Decay Rates in Colloidal Nanoplatelets by Time-Gated Photon Correlation
AU - Benjamin, Elad
AU - Yallapragada, Venkata Jayasurya
AU - Amgar, Daniel
AU - Yang, Gaoling
AU - Tenne, Ron
AU - Oron, Dan
N1 - Publisher Copyright:
Copyright © 2020 American Chemical Society.
PY - 2020/8/20
Y1 - 2020/8/20
N2 - Excitons in colloidal semiconductor nanoplatelets (NPLs) are weakly confined in the lateral dimensions. This results in significantly smaller Auger rates and, consequently, larger biexciton quantum yields, when compared to spherical quantum dots (QDs). Here we report a study of the temperature dependence of the biexciton Auger rate in individual CdSe/CdS core-shell NPLs, through the measurement of time-gated second-order photon correlations in the photoluminescence. We also utilize this method to directly estimate the single-exciton radiative rate. We find that whereas the radiative lifetime of NPLs increases with temperature, the Auger lifetime is almost temperature-independent. Our findings suggest that Auger recombination in NPLs is qualitatively similar to that of semiconductor quantum wells. Time-gated photon correlation measurements offer the unique ability to study multiphoton emission events, while excluding effects of competing fast processes, and can provide significant insight into the photophysics of a variety of nanocrystal multiphoton emitters.
AB - Excitons in colloidal semiconductor nanoplatelets (NPLs) are weakly confined in the lateral dimensions. This results in significantly smaller Auger rates and, consequently, larger biexciton quantum yields, when compared to spherical quantum dots (QDs). Here we report a study of the temperature dependence of the biexciton Auger rate in individual CdSe/CdS core-shell NPLs, through the measurement of time-gated second-order photon correlations in the photoluminescence. We also utilize this method to directly estimate the single-exciton radiative rate. We find that whereas the radiative lifetime of NPLs increases with temperature, the Auger lifetime is almost temperature-independent. Our findings suggest that Auger recombination in NPLs is qualitatively similar to that of semiconductor quantum wells. Time-gated photon correlation measurements offer the unique ability to study multiphoton emission events, while excluding effects of competing fast processes, and can provide significant insight into the photophysics of a variety of nanocrystal multiphoton emitters.
UR - http://www.scopus.com/inward/record.url?scp=85089768348&partnerID=8YFLogxK
U2 - 10.1021/acs.jpclett.0c01628
DO - 10.1021/acs.jpclett.0c01628
M3 - Article
C2 - 32693606
AN - SCOPUS:85089768348
SN - 1948-7185
VL - 11
SP - 6513
EP - 6518
JO - Journal of Physical Chemistry Letters
JF - Journal of Physical Chemistry Letters
IS - 16
ER -