Biexcitonic superfluorescence from CuCl quantum dots under resonant two-photon excitation
Biexcitonic superfluorescence from CuCl quantum dots under resonant two-photon excitation
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共振双光子激发下 CuCl 量子点的双激子超荧光
DOI：
10.1002/pssc.201000668
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
K.Miyajima
中科院分区：
文献类型：
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作者：
鳴海康雄;安村光正;野尻浩之;中村哲也;他合計 7 名;K.Miyajima
用光学克尔门方法测量了嵌在NaCl基质中的CuCl量子点中双激子的时间分辨光致发光谱。观察到双激子的共振双光子激发的超短脉冲发射。这种脉冲发射的峰值强度依赖于激发密度的四次方，这表明超荧光起源于相干耦合激发的量子点。这种脉冲发射的光子能量随着激发密度的增加而增加。这意味着超荧光有效地取决于点的尺寸，因为双激子直接由具有尺寸分布的量子点系综的共振双光子激发产生（© 2011 WILEY-VCH Verlag GmbH & Co. KGaA，魏因海姆）。
Time‐resolved photoluminescence spectra of biexcitons confined in CuCl quantum dots embedded in a NaCl matrix have been measured by an optical Kerr gate method. Ultrashort pulsed emission was observed for resonant two‐photon excitation of the biexcitons. The peak intensity of this pulsed emission depended on the fourth power of the excitation density, which indicates that the superfluorescence originates from coherently coupled excited quantum dots. The photon energy of this pulsed emission increased with increasing excitation density. This implies that the superfluorescence efficiently depends on the dot size because biexcitons are directly generated by resonant two‐photon excitation for an ensemble of quantum dots with a size distribution (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)