Mean Transverse Energy Measurement of Negative Electron Affinity GaAs-Based Photocathode
Mean Transverse Energy Measurement of Negative Electron Affinity GaAs-Based Photocathode
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DOI：
10.1143/jjap.51.046402
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发表时间：
2012-03
影响因子：
1.5
通讯作者：
S. Matsuba;Y. Honda;X. Jin;T. Miyajima;M. Yamamoto;T. Uchiyama;M. Kuwahara;Y. Takeda
中科院分区：
文献类型：
--
作者：
S. Matsuba;Y. Honda;X. Jin;T. Miyajima;M. Yamamoto;T. Uchiyama;M. Kuwahara;Y. Takeda
负电子亲和势GaAs光电阴极电子源具有高亮度、高量子效率和适中的时间响应的特点。初始发射度取决于阴极表面上的电子的平均横向能量（MTE）。我们评估的MTE的基础上获得的发射度测量使用腰部扫描方法与三种类型的阴极：体GaAs，厚度控制的样品与有源层厚度为100和1000 nm，和GaAs/GaAsP超晶格样品。阴极量子效率，激光波长，GaAs阴极活性层的厚度上的MTE的依赖关系进行了描述。在块状GaAs和厚度受控样品的情况下，确定厚度和阴极量子效率在测量误差内不影响MTE。另一方面，激光波长影响所有阴极的MTE。
A negative electron affinity GaAs photocathode electron source is characterized by high brightness, high quantum efficiency, and a moderate temporal response. The initial emittance depends on the mean transverse energy (MTE) of the electrons on the cathode surface. We evaluated the MTE based on emittance measurements obtained using the waist scan method with three types of cathodes: bulk GaAs, thickness-controlled samples with active-layer thicknesses of 100 and 1000 nm, and a GaAs/GaAsP superlattice sample. The dependence of the cathode quantum efficiency, the laser wavelength, and the thickness of the GaAs cathode active layer on the MTE are described. In the case of the bulk GaAs and the thickness-controlled samples, it was determined that the thickness and cathode quantum efficiency do not affect the MTE within the measurement error. The laser wavelength, on the other hand, affects the MTE of all cathodes.