驱动电压频率对固态阴极射线发光影响的研究

固态阴极射线发光(SSCL)是发光学中一种新的激发方式,引发出一些发光学中的重要问题,但是固态阴极射线发光的性质还不是十分清楚,需要进一步研究.文章用SiO2作为电子加速层,有机材料MEH-PPV为发光层,在正弦交流电压驱动下实现了固态阴极射线发光,得到410和580 nm两个发光峰.通过研究这两个发光峰的性质,证实它们分别符合能带理论和分子理论.改变驱动电压的频率时,长波峰的发光强度随频率的增加而增加,而短波峰的发光强度随频率的增加而减小,这是由于这两个发光峰对应的上能级寿命不同引起的.

The Influence of Frequency on Solid State Cathodoluminescence

Solid state cathodoluminescence(SSCL) is a new mechanism of light emission in organic-inorganic system.In the present article,we get SSCL under sinusoidal alternating-current voltage with a structure of ITO/SiO_2/MEH-PPV/SiO_2/Al. The spectra have two peaks: 410 and 580 nm,which obey molecular theory and band model,respectively.The temporal behaviors of both peaks in SSCL are studied with a new method of estimating lifetime in frequency domain.The intensity of the peak at 410 nm decreases as the frequency of the driving voltage increases,and the intensity of the peak at 580 nm increases as the frequency of the driving voltage increases.The difference in the dependence of light intensity on the frequency of excitation comes from the difference in the lifetime of the two peaks.The lifetime of short wavelength emission is found to be less than 5 ms while that of long wavelength emission is more than 0.05 ms.