Abstract
Quasi-two-dimensional nanoplatelets (NPLs) possess fundamentally different excitonic properties from zero-dimensional quantum dots. We study lateral size-dependent photon emission statistics and carrier dynamics of individual NPLs using second-order photon correlation (g(2)(Ï.,)) spectroscopy and photoluminescence (PL) intensity-dependent lifetime analysis. Room-temperature radiative lifetimes of NPLs can be derived from maximum PL intensity periods in PL time traces. It first decreases with NPL lateral size and then stays constant, deviating from the electric dipole approximation. Analysis of the PL time traces further reveals that the single exciton quantum yield in NPLs decreases with NPL lateral size and increases with protecting shell thickness, indicating the importance of surface passivation on NPL emission quality. Second-order photon correlation (g(2)(Ï.,)) studies of single NPLs show that the biexciton quantum yield is strongly dependent on the lateral size and single exciton quantum yield of the NPLs. In large NPLs with unity single exciton quantum yield, the corresponding biexciton quantum yield can reach unity. These findings reveal that by careful growth control and core-shell material engineering, NPLs can be of great potential for light amplification and integrated quantum photonic applications.
| Original language | English |
|---|---|
| Pages (from-to) | 9119-9127 |
| Number of pages | 9 |
| Journal | ACS Nano |
| Volume | 11 |
| Issue number | 9 |
| DOIs | |
| Publication status | Published - Sep 26 2017 |
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Keywords
- biexciton
- CdSe/CdS nanoplatelets
- exciton coherent motion area
- quasi-2D exciton
- radiative lifetime
- second-order photon correlation function
ASJC Scopus subject areas
- Materials Science(all)
- Engineering(all)
- Physics and Astronomy(all)
Cite this
Size-Dependent Biexciton Quantum Yields and Carrier Dynamics of Quasi-Two-Dimensional Core/Shell Nanoplatelets. / Ma, Xuedan; Diroll, Benjamin T.; Cho, Wooje; Fedin, Igor; Schaller, Richard D; Talapin, Dmitri V.; Gray, Stephen K.; Wiederrecht, Gary P.; Gosztola, David J.
In: ACS Nano, Vol. 11, No. 9, 26.09.2017, p. 9119-9127.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Size-Dependent Biexciton Quantum Yields and Carrier Dynamics of Quasi-Two-Dimensional Core/Shell Nanoplatelets
AU - Ma, Xuedan
AU - Diroll, Benjamin T.
AU - Cho, Wooje
AU - Fedin, Igor
AU - Schaller, Richard D
AU - Talapin, Dmitri V.
AU - Gray, Stephen K.
AU - Wiederrecht, Gary P.
AU - Gosztola, David J.
PY - 2017/9/26
Y1 - 2017/9/26
N2 - Quasi-two-dimensional nanoplatelets (NPLs) possess fundamentally different excitonic properties from zero-dimensional quantum dots. We study lateral size-dependent photon emission statistics and carrier dynamics of individual NPLs using second-order photon correlation (g(2)(Ï.,)) spectroscopy and photoluminescence (PL) intensity-dependent lifetime analysis. Room-temperature radiative lifetimes of NPLs can be derived from maximum PL intensity periods in PL time traces. It first decreases with NPL lateral size and then stays constant, deviating from the electric dipole approximation. Analysis of the PL time traces further reveals that the single exciton quantum yield in NPLs decreases with NPL lateral size and increases with protecting shell thickness, indicating the importance of surface passivation on NPL emission quality. Second-order photon correlation (g(2)(Ï.,)) studies of single NPLs show that the biexciton quantum yield is strongly dependent on the lateral size and single exciton quantum yield of the NPLs. In large NPLs with unity single exciton quantum yield, the corresponding biexciton quantum yield can reach unity. These findings reveal that by careful growth control and core-shell material engineering, NPLs can be of great potential for light amplification and integrated quantum photonic applications.
AB - Quasi-two-dimensional nanoplatelets (NPLs) possess fundamentally different excitonic properties from zero-dimensional quantum dots. We study lateral size-dependent photon emission statistics and carrier dynamics of individual NPLs using second-order photon correlation (g(2)(Ï.,)) spectroscopy and photoluminescence (PL) intensity-dependent lifetime analysis. Room-temperature radiative lifetimes of NPLs can be derived from maximum PL intensity periods in PL time traces. It first decreases with NPL lateral size and then stays constant, deviating from the electric dipole approximation. Analysis of the PL time traces further reveals that the single exciton quantum yield in NPLs decreases with NPL lateral size and increases with protecting shell thickness, indicating the importance of surface passivation on NPL emission quality. Second-order photon correlation (g(2)(Ï.,)) studies of single NPLs show that the biexciton quantum yield is strongly dependent on the lateral size and single exciton quantum yield of the NPLs. In large NPLs with unity single exciton quantum yield, the corresponding biexciton quantum yield can reach unity. These findings reveal that by careful growth control and core-shell material engineering, NPLs can be of great potential for light amplification and integrated quantum photonic applications.
KW - biexciton
KW - CdSe/CdS nanoplatelets
KW - exciton coherent motion area
KW - quasi-2D exciton
KW - radiative lifetime
KW - second-order photon correlation function
UR - http://www.scopus.com/inward/record.url?scp=85029935706&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85029935706&partnerID=8YFLogxK
U2 - 10.1021/acsnano.7b03943
DO - 10.1021/acsnano.7b03943
M3 - Article
C2 - 28787569
AN - SCOPUS:85029935706
VL - 11
SP - 9119
EP - 9127
JO - ACS Nano
JF - ACS Nano
SN - 1936-0851
IS - 9
ER -