无激光条件下的相位锁定光子-电子相互作用
Phase-locked photon-electron interaction without a laser
AI总结：
提出基于阴极荧光光谱的逆向方法，利用电子驱动光子源在电子显微镜中产生相位锁定光子，实现无激光条件下的光子-电子相互作用，并验证了高达27%的相互相干度，为量子材料的局部光谱研究开辟新途径。
摘要：
电子显微镜中的超快电子-光子光谱通常需要超快激光装置。来自工程电子源的光发射被用于产生脉冲电子，这些电子与在指定时间延迟下被超快激光脉冲激发的样品发生相互作用。因此，开发超快电子显微镜需要利用外部激光激发和复杂的同步方案。在此，我们提出了一种基于阴极荧光光谱的逆向方法，以在电子显微镜中引入内部辐射源。我们的方法基于电子束与电子驱动光子源（EDPHS）和待测样品的顺序相互作用。电子显微镜中的电子驱动光子源产生相位锁定光子，这些光子与快速电子的近场分布相互相干。由于它们具有不同的速度，可以通过改变EDPHS与样品之间的距离来轻松改变到达样品的光子和电子之间的延迟。我们通过使用EDPHS和WSe2薄片的组合系统进行干涉测量，证明了EDPHS和样品辐射之间的相互相干性。我们断言EDPHS和样品辐射的相互频率和动量依赖相关性，并在实验上确定了高达27%的相互相干度。这种水平的相互相干性使我们能够在电子显微镜中进行光谱干涉测量。我们的方法具有简单、紧凑和使用连续电子束操作的优点。它将为量子材料、单光子系统和相干激子-极化样品的局部电子-光子相关光谱打开纳米级分辨率的大门。
英文摘要：
Ultrafast electron-photon spectroscopy in electron microscopes commonly requires ultrafast laser setups. Photoemission from an engineered electron source is used to generate pulsed electrons, interacting with a sample that is excited by the ultrafast laser pulse at a specified time delay. Thus, developing an ultrafast electron microscope demands the exploitation of extrinsic laser excitations and complex synchronization schemes. Here, we present an inverse approach based on cathodoluminescence spectroscopy to introduce internal radiation sources in an electron microscope. Our method is based on a sequential interaction of the electron beam with an electron-driven photon source (EDPHS) and the investigated sample. An electron-driven photon source in an electron microscope generates phase-locked photons that are mutually coherent with the near-field distribution of the swift electron. Due to their different velocities, one can readily change the delay between the photons and electrons arriving at the sample by changing the distance between the EDPHS and the sample. We demonstrate the mutual coherence between the radiations from the EDPHS and the sample by performing interferometry with a combined system of an EDPHS and a WSe2 flake. We assert the mutual frequency and momentum-dependent correlation of the EDPHS and sample radiation, and determine experimentally the degree of mutual coherence of up to 27%. This level of mutual coherence allows us to perform spectral interferometry with an electron microscope. Our method has the advantage of being simple, compact and operating with continuous electron beams. It will open the door to local electron-photon correlation spectroscopy of quantum materials, single photon systems, and coherent exciton-polaritonic samples with nanometric resolution.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
