OPTICAL SPECTROSCOPY OF EXTRINSIC RECOMBINATIONS IN GALLIUM SELENIDE
OPTICAL SPECTROSCOPY OF EXTRINSIC RECOMBINATIONS IN GALLIUM SELENIDE
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DOI：
10.1103/physrevb.40.3182
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发表时间：
1989-08-15
影响因子：
3.7
通讯作者：
MONTAGNA, M
中科院分区：
文献类型：
--
作者：
CAPOZZI, V;MONTAGNA, M
已经研究了 GaSe 晶体中能量低于吸收边的发光，该晶体含有不同程度的晶格无序，作为温度、光激发强度和激发能的函数。在低激发强度下，外在发光由宽重叠带组成，当温度升高时，这些带呈现蓝移。它们的形状和强度很大程度上取决于激光激发频率和晶格无序程度。结果根据涉及浅施主和自由电子与深受主重组的模型进行了讨论。发现这两种复合机制以及涉及自由和束缚激子的复合机制是竞争性的。它们的相对重要性很大程度上取决于结构缺陷的浓度、温度、激发强度和激发频率。
Luminescence at energy lower than the absorption edge has been investigated in crystals of GaSe, containing different degrees of lattice disorder, as a function of temperature, of photoexcitation intensity, and of excitation energy. At low excitation intensity, the extrinsic luminescence is composed of broad overlapping bands that present a blue shift when the temperature increases. Their shape and intensity is strongly dependent on the laser excitation frequency and on the degree of lattice disorder. The results are discussed in terms of a model involving the recombination of shallow donors and free electrons with deep acceptors. These two recombination mechanisms and those involving free and bound excitons are found to be competitive. Their relative importance is strongly dependent on the concentration of structural defects, on the temperature, on the excitation intensity, and on the excitation frequency.