Few-electron correlations after ultrafast photoemission from nanometric needle tips
Few-electron correlations after ultrafast photoemission from nanometric needle tips
复制标题
纳米针尖超快光发射后的少电子相关性
作者：
S. Meier;J. Heimerl;P. Hommelhoff
自由电子在电子显微镜、加速器和光电子能谱等各种应用中是必不可少的。然而，许多电子的空间电荷效应通常是一个问题，当被限制在极小的时空维度时，即使是两个电子也可以强烈地相互作用。在这里，我们证明了由此产生的库仑排斥可以是非常有利的，因为它会导致强的电子-电子相关。我们发现，飞秒激光发射的电子从纳米针尖是高度相关的能量，因为动态库仑排斥，与可见度为56%。我们提取的平均能量分裂为3.3 eV和82 fs的相关衰减时间。能量滤波后的电子呈现亚泊松分布，其二阶相关函数g（2）= 0.34，表明通过简单的能量滤波可以实现散粒噪声的抑制。我们还达到强场制度的激光驱动的电子发射和获得洞察力如何不同的电子类（直接或再散射）的电子相关性的强激光场的影响。即使是几个电子被限制在一个紧密的空间和时间间隔强烈相互作用，往往会导致应用程序的问题。由此产生的排斥现在已经被证明允许强的电子-电子相关性，从而能够减少散粒噪声。
Free electrons are essential in such diverse applications as electron microscopes, accelerators and photoemission spectroscopy. However, the space charge effects of many electrons are often a problem and, when confined to extremely small space–time dimensions, even two electrons can interact strongly. Here we demonstrate that the resulting Coulomb repulsion can be highly advantageous, as it leads to strong electron–electron correlations. We show that femtosecond laser-emitted electrons from nanometric needle tips are highly anticorrelated in terms of energy because of dynamic Coulomb repulsion, with a visibility of 56%. We extract a mean energy splitting of 3.3 eV and a correlation decay time of 82 fs. The energy-filtered electrons display a sub-Poissonian number distribution with a second-order correlation function as small as g(2) = 0.34, implying that shot-noise-reduced pulsed electron beams can be realized by simple energy filtering. We also reach the strong-field regime of laser-driven electron emission and gain insights into how the electron correlations of the different electron classes (direct or rescattered) are influenced by the strong laser fields. Even a few electrons confined to a tight space and time interval interact strongly, often causing issues for applications. The resulting repulsion has now been shown to allow strong electron–electron correlations, enabling shot-noise reduction.
影响因子：
19.6
作者：
Ludwig, Markus;Aguirregabiria, Garikoitz;Brida, Daniele
通讯作者：
Brida, Daniele
影响因子：
64.8
作者：
Bloch, Jacqueline;Cavalleri, Andrea;Rubio, Angel
通讯作者：
Rubio, Angel
影响因子：
7
作者：
Duchet, Maxime;Perisanu, Sorin;Ayari, Anthony
通讯作者：
Ayari, Anthony