Dynamical process of exciton–exciton scattering in CuI thin films
Dynamical process of exciton–exciton scattering in CuI thin films
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DOI：
10.1016/j.jlumin.2006.01.151
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发表时间：
2007
影响因子：
3.6
通讯作者：
H. Ichida;T. Shimomura;K. Mizoguchi;Daegwi Kim;Y. Kanematsu;M. Nakayama
中科院分区：
文献类型：
--
作者：
H. Ichida;T. Shimomura;K. Mizoguchi;Daegwi Kim;Y. Kanematsu;M. Nakayama
我们研究了CuI薄膜在高达25ps强激发条件下的时间分辨光致发光(PL)光谱。在时间积分光致发光谱中，我们清楚地观察到了发光带来源于激子的非弹性散射，即P发射。用光学克尔门方法得到的时间分辨光致发光光谱表明，P发射带的峰值能量在皮秒范围内随时间变化，反映了激子系统有效温度的变化。在P发射带的时间分布中，我们发现了以下两个特征特性。其一是衰减时间几乎不依赖于激励功率。另一种是随着励磁功率的增加，上升时间变得相当快。此外，我们还发现P发射上升时间的倒数几乎与激发功率成二次关系。
We have investigated the time-resolved photoluminescence (PL) spectra of CuI thin films under intense excitation conditions in the time region up to 25ps. In the time-integrated PL spectra, we have clearly observed the PL band originated from the inelastic scattering of excitons, so-called P emission. The time-resolved PL spectra obtained by using an optical Kerr gating method exhibit that the peak energy of the P-emission band temporally changes in a picosecond region, which reflects the variation of the effective temperature of excitonic system. In the time profile of the P-emission band, we found the following two characteristic properties. One is that the decay time hardly depends on the excitation power. The other is that the rise time becomes considerably faster with increasing excitation power. Moreover, we have found that the inverse of the rise time of the P emission exhibits an almost quadratic dependence on the excitation power.