超高真空系统中GaAlAs光电阴极的重新铯化研究

为了探索在超高真空系统中使用稳定性和重复性好的光电阴极,开展了金属有机化学气相沉积生长的反射式GaAlAs和GaAs光电阴极的激活实验和重新铯化实验,测试了Cs/O激活后和重新补Cs后的光谱响应曲线和光电流衰减曲线.实验结果表明,在100 lx白光照射条件下,超高真空环境中的GaAlAs光电阴极在Cs/O激活后和重新补Cs激活后的光电流衰减寿命相比GaAs光电阴极更长,并且在多次补Cs激活后呈现较一致的蓝绿光响应能力和光电流衰减寿命,体现了GaAlAs光电阴极在真空系统中稳定性和可重复性使用方面具有的优越性,为海洋真空探测器件和真空电子源领域的研究提供了实验指导.

Recesiation of GaAlAs photo catho des in an ultrahigh vacuum system

To seek a photocathode with good stability and repeatability in an ultrahigh vacuum system, activation and recesiation experiments are carried out on reflection-mode GaAlAs and GaAs photocathodes grown by metalorganic chemical vapor deposition, and the spectral response curves and photocurrent decay curves are measured after Cs/O activation and recesiation. Experimental results show that the photocurrent decay lifetime for GaAlAs photocathode illuminated by white light with an intensity of 100 lx is longer than that for GaAs photocathode after Cs/O activation and recesiation under ultrahigh vacuum condition. Moreover, GaAlAs photocathode exhibits a coincident blue-green response capability and a photocurrent decay lifetime after multiple recesiations, reflecting the superiority in stability and repeatability for GaAlAs photocathode operating in the vacuum system, and may provide an experimental guidance for exploring marine vacuum detectors and vacuum electron sources.
Keywords：GaAlAs photocathodephotocurrent decayrecesiationspectral response