为了研究镧钼阴极表面发射机制, 利用新型阴极研究装置研究阴极发射性能与表面元素La, O比例的关系, 发现表面层中La/O比例越高, 阴极的发射性能越好. 在实验基础上提出了金属La超微粒子埋藏于La2O3晶体中的热阴极表面发射模型, 模型认为活性层中的超额镧以镧超微粒子形式存在, La超微粒子中的电子在热激发下越过肖特基势垒进入La2O3晶体的导带进而克服表面电子亲和势逸出到真空, 提供了电子发射的丰富源泉. 由于肖特基势垒远小于La2O3的禁带宽度, 并且超微粒子可以使耗尽层厚度变薄, 极大降低了电子发射到真空的阈值.
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