Exciton-carrier scattering in gallium selenide.
Exciton-carrier scattering in gallium selenide.
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硒化镓中的激子载流子散射。
DOI：
10.1103/physrevb.47.6340
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Staehli
中科院分区：
文献类型：
--
作者：
Capozzi;Pavesi;Staehli
详细研究了由于激子自由载流子过程中的复合发光的特点。该过程显示出良好分辨的发光线，并且即使在低温下，该半导体中也是有效的复合过程。我们报告准确的光致发光光谱测量在2 K作为一个函数的激发强度，激发能量，和晶格温度从2到200 K。为了区分不同种类的自由载流子参与激子载流子散射在GaSe中，我们已经计算了不同的载体的直接激子的散射概率的温度依赖性：直接电子，间接电子，和空穴，我们发现，最可能的激子载流子散射过程是涉及共存的直接电子和空穴碰撞。计算了激子-载流子散射的线形随载流子温度的变化，并与实验的发光光谱（2 ~ 200 K）进行了拟合，发现符合很好.从GaSe的吸收光谱中，我们得到了激子极化率的直接估计.
Detailed investigation of the luminescence features due to the recombination of the exciton-free-carrier process in GaSe is presented. This process shows a well-resolved luminescence line and it is an efficient recombination process in this semiconductor, even at low temperatures. We report accurate photoluminescence spectra measured at 2 K as a function of the excitation intensity, of the excitation energy, and of the lattice temperature from 2 to 200 K. To discriminate between the different kinds of free carriers participating in exciton-carrier scattering in GaSe, we have computed the temperature dependence of the scattering probability of the direct excitons with different carriers: direct electrons, indirect electrons, and holes; we have found that the most probable exciton-carrier scattering process is that involving the coexistence of direct electron and hole collisions. Line shape of the exciton-carrier scattering as a function of the carrier temperature has been calculated and fitted to the experimental luminescence spectra from 2 to 200 K and a very good agreement is found. From the absorption spectra of GaSe, we obtained a direct estimate of the excitonic polarizability.