Coherent dynamics of excitons and excitonic complexes in ZnSe epilayers
Coherent dynamics of excitons and excitonic complexes in ZnSe epilayers
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ZnSe 外延层中激子和激子复合物的相干动力学
DOI：
10.1364/josab.13.001256
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发表时间：
1996
影响因子：
1.9
通讯作者：
D. Hommel
中科院分区：
文献类型：
--
作者：
U. Neukirch;D. Weckendrup;K. Wundke;J. Gutowski;D. Hommel
在高质量双轴应变 ZnSe 层中研究了束缚激子和双激子对简并四波混频信号的贡献。对于前一种配合物，在时间分辨四波混频中发现了与自由激子偏振干涉的特征，而光谱分辨数据则表明发生了量子跳动。因此，该系统一方面表现为独立的两能级系统，另一方面表现为三能级系统的混合体。双激子主要在激励脉冲之间的负延迟处对信号做出贡献，并通过光谱分辨测量和使用不同的脉冲极化配置来识别。双激子（和激子）的选择规则与实验数据完全一致。
The contribution of bound excitons and biexcitons to degenerate four-wave mixing signals is investigated in high-quality biaxially strained ZnSe layers. For the former complexes signatures of polarization interference with free excitons are found in time-resolved four-wave mixing, whereas spectrally resolved data point to the occurrence of quantum beating. Thus this system behaves as a mixture of independent two-level systems on the one hand and three-level systems on the other. Biexcitons contribute to the signal mainly at negative delay between the exciting pulses and are identified by means of spectrally resolved measurements and by use of different configurations of the pulse polarization. Complete agreement is found between the selection rules for biexcitons (and excitons) and the experimental data.