Atomically resolved EMCD on ferrimagnets measured with electron vortex beams

使用电子涡流束测量亚铁磁体上的原子分辨 EMCD

• 批准号: 504660779
• 负责人: Dr. Darius Pohl
• 金额: --
• 依托单位: Center for Advancing Electronics Dresden (cfaed)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/504660779?language=en
• 关键词: Atomically; resolved; EMCD; ferrimagnets; measured

Electron vortex beams (EVBs) carry a discrete orbital angular momentum (OAM), L, and are predicted to reveal electron energy loss magnetic chiral dichroism (EMCD) upon interacting with magnetic samples down to the atomic scale. However, proof-of-concept experiments so far failed since the weak magnetic signal is still hidden behind the poor signal-to-noise ratio (SNR) of the acquired spectra. Within this project we therefore seek to develop strategies to improve the SNR on the methodical side as well as on the materials side – both of which are essential for a successful proof-of-concept experiment. We anticipate to build a fundamental understanding of how electron vortex beams with high spatial coherence and purity can be generated and how different material properties impact on the SNR for the detection of an atomically resolved EMCD signal.

电子涡旋束（EVBs）进行离散的轨道角动量（OAM），L，并预测揭示电子能量损失磁手征二向色性（EMCD）与磁性样品相互作用后，下降到原子尺度。然而，到目前为止，概念验证实验失败了，因为微弱的磁信号仍然隐藏在所获得的光谱的低信噪比（SNR）后面。因此，在这个项目中，我们寻求制定策略，以提高SNR的方法方面以及材料方面-这两者都是一个成功的概念验证实验所必需的。我们期望建立一个基本的理解，如何产生具有高空间相干性和纯度的电子涡旋束，以及不同的材料特性如何影响SNR的原子分辨EMCD信号的检测。