探索热力学LabB6虚拟源模式电子枪的潜力,用于高角电流密度和狭窄的能量分布
Ha Rim Lee1, Junhyeok Hwang1, Takashi Ogawa1,2
1Scientific Instruments Performance Evaluation Team, Advanced Instrumentation Institute, Korea Research Institute of Standards and Science (KRISS), 267 Gajeong-ro, Yuseong-gu, Daejeon 34113, South Korea.
概括
兰六化物 (LaB6) 电子源在虚拟源模式中表现最好,实现显著更高的亮度和稳定性. 这种模式提供了与Schottky源相提并论的性能,解锁了LaB6.
科学领域:
- 材料科学 材料科学 材料科学
- 物理 物理学 物理
- 电子光学 电子光学
背景情况:
- 兰六化物 (LaB6) 热电子源提供比更高的亮度,但与肖特基源相比性能较差.
- 由于运行限制,LaB6电子源的全部潜力在很大程度上仍未得到开发.
- 优化操作条件对于提高LaB6电子源性能至关重要.
研究的目的:
- 研究LaB6电子源在各种工作条件下的性能.
- 为了弥合LaB6和Schottky电子源之间的性能差距.
- 通过优化操作实现LaB6电子源的全部潜力.
主要方法:
- 模拟在虚拟源模式下进行,以分析光束亮度和半角.
- 电子能量的分布是用预镜减速场能量分析仪测量.
- 虚拟源和交叉模式的稳定性得到了定量评估.
主要成果:
- 虚拟源模式模拟显示光束亮度增加和光束半角减少,提取电压更高,承诺亮度比交叉模式增加十倍.
- 在虚拟源模式下进行的测量结果显示,能量分布为0.55 eV,角电流密度为33 mA/sr.
- 与交叉模式 (±0.138%) 相比,虚拟源模式显示出更高的稳定性 (±0.022%).
结论:
- LaB6电子源的虚拟源模式提供了与肖特基电子枪相比较的狭窄能量分布.
- LaB6虚拟源模式提供比Schottky源高2000倍以上的角电流密度.
- 在虚拟源模式中的优化操作显著提高了LaB6电子源的功能,使它们与先进的电子源竞争.
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