Highly emissive multiexcitons in steady-state photoluminescence of individual "giant" CdSe/CdS Core/Shell nanocrystals.
Highly emissive multiexcitons in steady-state photoluminescence of individual "giant" CdSe/CdS Core/Shell nanocrystals.
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DOI：
10.1021/nl1004652
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发表时间：
2010-07-14
期刊：
影响因子：
10.8
通讯作者：
Klimov VI
中科院分区：
文献类型：
--
作者：
Htoon H;Malko AV;Bussian D;Vela J;Chen Y;Hollingsworth JA;Klimov VI
开发具有抑制非辐射俄歇复合的纳米晶体量子点（NQDs）已成为胶体纳米结构研究的一个重要目标，这是由于激光器件、发光二极管和光伏电池的潜在应用需求所驱动的。在这里，我们对最近开发的核-壳NQDs（所谓的“巨型”NQDs）进行了单纳米晶体光谱研究，这些NQDs由一个小的CdSe核心组成，周围是16层单层厚的CdS壳。通过连续波和脉冲激发，我们观察到中性和带电双激子以及高阶多激子的强发射特征。在单个纳米晶体的稳态光致发光中，明显的多激子峰的发展，以及在高泵浦水平范围内发射强度的持续增长，指向非辐射俄歇衰变的显著抑制，通常使多激子不发射。这些系统中异常高的多激子发射效率为使用成熟的单点光谱方法研究多激子现象提供了有趣的机会，以及新的令人兴奋的应用前景，这些应用以前受到非辐射俄歇衰变的阻碍。
The development of nanocrystal quantum dots (NQDs) with suppressed nonradiative Auger recombination has been an important goal in colloidal nanostructure research motivated by the needs of prospective applications in lasing devices, light emitting diodes, and photovoltaic cells. Here, we conduct single-nanocrystal spectroscopic studies of recently developed core-shell NQDs (so-called “giant” NQDs) that comprise a small CdSe core surrounded by a 16-monolayer-thick CdS shell. Using both continuous-wave and pulsed excitation, we observe strong emission features due both to neutral and charged biexcitons, as well as multiexcitons of higher order. The development of pronounced multiexcitonic peaks in steady-state photoluminescence of individual nanocrystals, as well as continuous growth of the emission intensity in the range of high pump levels, point toward a significant suppression of nonradiative Auger decay that normally renders multiexcitons nonemissive. The unusually high multiexciton emission efficiencies in these systems open interesting opportunities for studies of multiexciton phenomena using well-established methods of single-dot spectroscopy, as well as new exciting prospects for applications, that have previously been hampered by nonradiative Auger decay.
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DOI：
10.1016/s1386-9477(02)00374-0
发表时间：
2002-04-01
影响因子：
3.3
作者：
Nozik, AJ
通讯作者：
Nozik, AJ
影响因子：
3.7
作者：
Klimov, V. I.;McGuire, J. A.;Rupasov, V. I.
通讯作者：
Rupasov, V. I.
影响因子：
29.4
作者：
Kazes, M;Lewis, DY;Banin, U
通讯作者：
Banin, U
影响因子：
64.8
作者：
Nirmal, M;Dabbousi, BO;Brus, LE
通讯作者：
Brus, LE
影响因子：
64.8
作者：
COLVIN, VL;SCHLAMP, MC;ALIVISATOS, AP
通讯作者：
ALIVISATOS, AP