Abstract
Many potential applications of semiconductor nanocrystals are hindered by nonradlative Auger recombination wherein the electron-hole (exciton) recombination energy is transferred to a third charge carrier. This process severely limits the lifetime and bandwidth of optical gain, leads to large nonradiative losses in light-emitting diodes and photovoltaic cells, and Is believed to be responsible for intermittency ("blinking") of emission from single nanocrystals. The development of nanostructures in which Auger recombination is suppressed has recently been the subject of much research in the colloidal nanocrystal field. Here, we provide direct experimental evidence that so-called "giant" nanocrystals consisting of a small CdSe core and a thick CdS shell exhibit a significant (orders of magnitude) suppression of Auger decay rates. As a consequence, even multiexcitons of a very high order exhibit significant emission efficiencies, which allows us to demonstrate optical amplification with an extraordinarily large bandwidth (>500 meV) and record low excitation thresholds. This demonstration represents an important milestone toward practical lasing technologies utilizing solution-processable colloidal nanoparticles.
| Original language | English |
|---|---|
| Pages (from-to) | 3482-3488 |
| Number of pages | 7 |
| Journal | Nano Letters |
| Volume | 9 |
| Issue number | 10 |
| DOIs | |
| Publication status | Published - Oct 14 2009 |
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ASJC Scopus subject areas
- Condensed Matter Physics
- Bioengineering
- Chemistry(all)
- Materials Science(all)
- Mechanical Engineering
Cite this
Suppressed auger recombination in "Giant" nanocrystals boosts optical gain performance. / García-Santamaría, Florencio; Chen, Yongfen; Vela, Javier; Schaller, Richard D; Hollingsworth, Jennifer A.; Klimov, Victor I.
In: Nano Letters, Vol. 9, No. 10, 14.10.2009, p. 3482-3488.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Suppressed auger recombination in "Giant" nanocrystals boosts optical gain performance
AU - García-Santamaría, Florencio
AU - Chen, Yongfen
AU - Vela, Javier
AU - Schaller, Richard D
AU - Hollingsworth, Jennifer A.
AU - Klimov, Victor I
PY - 2009/10/14
Y1 - 2009/10/14
N2 - Many potential applications of semiconductor nanocrystals are hindered by nonradlative Auger recombination wherein the electron-hole (exciton) recombination energy is transferred to a third charge carrier. This process severely limits the lifetime and bandwidth of optical gain, leads to large nonradiative losses in light-emitting diodes and photovoltaic cells, and Is believed to be responsible for intermittency ("blinking") of emission from single nanocrystals. The development of nanostructures in which Auger recombination is suppressed has recently been the subject of much research in the colloidal nanocrystal field. Here, we provide direct experimental evidence that so-called "giant" nanocrystals consisting of a small CdSe core and a thick CdS shell exhibit a significant (orders of magnitude) suppression of Auger decay rates. As a consequence, even multiexcitons of a very high order exhibit significant emission efficiencies, which allows us to demonstrate optical amplification with an extraordinarily large bandwidth (>500 meV) and record low excitation thresholds. This demonstration represents an important milestone toward practical lasing technologies utilizing solution-processable colloidal nanoparticles.
AB - Many potential applications of semiconductor nanocrystals are hindered by nonradlative Auger recombination wherein the electron-hole (exciton) recombination energy is transferred to a third charge carrier. This process severely limits the lifetime and bandwidth of optical gain, leads to large nonradiative losses in light-emitting diodes and photovoltaic cells, and Is believed to be responsible for intermittency ("blinking") of emission from single nanocrystals. The development of nanostructures in which Auger recombination is suppressed has recently been the subject of much research in the colloidal nanocrystal field. Here, we provide direct experimental evidence that so-called "giant" nanocrystals consisting of a small CdSe core and a thick CdS shell exhibit a significant (orders of magnitude) suppression of Auger decay rates. As a consequence, even multiexcitons of a very high order exhibit significant emission efficiencies, which allows us to demonstrate optical amplification with an extraordinarily large bandwidth (>500 meV) and record low excitation thresholds. This demonstration represents an important milestone toward practical lasing technologies utilizing solution-processable colloidal nanoparticles.
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U2 - 10.1021/nl901681d
DO - 10.1021/nl901681d
M3 - Article
VL - 9
SP - 3482
EP - 3488
JO - Nano Letters
JF - Nano Letters
SN - 1530-6984
IS - 10
ER -