固态阴极射线发光的表征

Characterization of solid state cathodoluminescence

固态阴极射线发光(SSCL)是一种全新的激发方式,是发光的一个分支.文章作者辨认了固态阴极射线发光的本质,证明了它的普适性.文章对固态阴极射线发光的本质作了进一步的分析,分析了它的发光光谱及随驱动电压提高时的变化规律,证明了固态阴极射线激发既可引起激子发光,又可引起扩展态发光,扩展态的发光是激子离化后产生的电子-空穴的直接复合.文章作者还研究了固态阴极射线发光的瞬态特性及发光的衰减,证明了在它的发光波形中用传统的位相方法已不能表示固态阴极射线发光与激发电压的时间关系,并从它的两个发光峰随频率变化的明显差别提出了实测真实发光寿命的思路.

The character of solid state cathodoluminescence （SSCL）, a new excitation mechanism of luminescence, has been identified and its universality demonstrated. The spectrum of SSCL and its change in behavior with the increase of driving voltage have been analyzed in detail. It is shown that SSCL includes the luminescence from exciton recombination and expanded state recombination. Under a high electric field, excitons dissociate to electrons and holes in expanded states, which results in luminescence from the expanded state recombination. The transient and decay characteristics of SSCL have also been investigated. It is concluded that the traditional phase method cannot be used to assess the temporal relationship between SSCL and the driving voltage. From the variation of SSCL with the excitation driving frequency we propose a new method to measure the true luminescence lifetime.