Hao Guanghui, Shi Feng, Cheng Hongchang, Ren Bin, Chang Benkang
Appl Opt. 2015 Apr 1;54(10):2572-6. doi: 10.1364/AO.54.002572.
In order to research a high-efficiency AlGaN photocathode, the AlGaN photocathodes with varied Al composition (0.68 and 0.4) and uniform Al composition (0.24) were grown. The photocathodes were activated by Cs adsorption and received their spectral response via multi-information system. Results show that the absorption rate of the AlGaN photocathode with varied Al composition is half of the AlGaN photocathode with uniform Al composition, but the quantum efficiency of the photocathode with varied Al composition is approximately 29% higher than that of the photocathode with uniform Al composition. The built-in field within the emission layer of the AlGaN photocathode with varied Al composition is much higher than that of the photocathode with uniform Al composition, which is the main factor that promotes the photoelectron movement toward the photocathode surface and improves photoemission performance of the AlGaN photocathode.
为了研究一种高效的AlGaN光电阴极，生长了具有不同Al组分（0.68和0.4）以及均匀Al组分（0.24）的AlGaN光电阴极。通过Cs吸附对光电阴极进行激活，并通过多信息系统获得其光谱响应。结果表明，具有不同Al组分的AlGaN光电阴极的吸收率是具有均匀Al组分的AlGaN光电阴极吸收率的一半，但具有不同Al组分的光电阴极的量子效率比具有均匀Al组分的光电阴极的量子效率高约29%。具有不同Al组分的AlGaN光电阴极发射层内的内建场远高于具有均匀Al组分的光电阴极，这是促进光电子向光电阴极表面移动并提高AlGaN光电阴极光发射性能的主要因素。
