Multiple exciton generation in nano-crystals revisited: Consistent calculation of the yield based on pump-probe spectroscopy

被引：36

作者：

Karki, Khadga J. ^{[1
]}

Ma, Fei ^{[1
]}

Zheng, Kaibo ^{[1
]}

Zidek, Karel ^{[1
]}

Mousa, Abdelrazek ^{[1
]}

Abdellah, Mohamed A. ^{[1
,4
]}

Messing, Maria E. ^{[2
]}

Wallenberg, L. Reine ^{[3
]}

Yartsev, Arkadi ^{[1
]}

Pullerits, Tonu ^{[1
]}

机构：

[1] Lund Univ, Dept Chem Phys, S-22100 Lund, Sweden

[2] Lund Univ, S-22100 Lund, Sweden

[3] Lund Univ, Ctr Anal & Synth nCHREM, S-22100 Lund, Sweden

[4] South Valley Univ, Qena Fac Sci, Dept Chem, Qena 83523, Egypt

来源：

SCIENTIFIC REPORTS | 2013年 / 3卷

基金：

瑞典研究理事会;

关键词：

CARRIER-MULTIPLICATION; QUANTUM DOTS; PBSE;

D O I：

10.1038/srep02287

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Multiple exciton generation (MEG) is a process in which more than one exciton is generated upon the absorption of a high energy photon, typically higher than two times the band gap, in semiconductor nanocrystals. It can be observed experimentally using time resolved spectroscopy such as the transient absorption measurements. Quantification of the MEG yield is usually done by assuming that the bi-exciton signal is twice the signal from a single exciton. Herein we show that this assumption is not always justified and may lead to significant errors in the estimated MEG yields. We develop a methodology to determine proper scaling factors to the signals from the transient absorption experiments. Using the methodology we find modest MEG yields in lead chalcogenide nanocrystals including the nanorods.

引用

页数：5

共 25 条

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