Picosecond dynamics of hot carriers and phonons and scintillator non-proportionality
Picosecond dynamics of hot carriers and phonons and scintillator non-proportionality
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DOI：
10.1063/1.4749253
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发表时间：
2012-06
影响因子：
3.2
通讯作者：
A. Kozorezov;J. Wigmore;A. Owens
中科院分区：
文献类型：
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作者：
A. Kozorezov;J. Wigmore;A. Owens
我们开发了一个模型，描述基于非热化载流子和声子传输的闪烁体中的非比例响应。我们表明，光子吸收后闪烁体中立即产生的 e-h 分布的热化可能比非比例信号形成的时间更长。在此期间，载流子和LO声子分布在远超过室温的准平衡温度下保持非简并。我们求解描述电子/空穴和声子的热双极等离子体中能量交换的平衡方程。考虑到动态筛选，我们计算了所有温度下的双极扩散系数。 NaI 的非比例光产率计算结果与实验数据一致。我们讨论非平衡模型的含义，将其预测与基于热化载流子传输的模型进行比较。最后，形状表明了非平衡效应的证据......
We have developed a model describing the non-proportional response in scintillators based on non-thermalised carrier and phonon transport. We show that the thermalization of e-h distributions produced in scintillators immediately after photon absorption may take longer than the period over which the non-proportional signal forms. The carrier and LO-phonon distributions during this period remain non-degenerate at quasi-equilibrium temperatures far exceeding room temperature. We solve balance equations describing the energy exchange in a hot bipolar plasma of electrons/holes and phonons. Taking into account dynamic screening, we calculate the ambipolar diffusion coefficient at all temperatures. The non-proportional light yields calculated for NaI are shown to be consistent with experimental data. We discuss the implications of a non-equilibrium model, comparing its predictions with a model based on the transport of thermalised carriers. Finally, evidence for non-equilibrium effects is suggested by the shape...