【摘 要】
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Observing the motion of electrons on their natural nanometer length and femtosecond time scales is a fundamental goal of and an open challenge for contemporary
【机 构】
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Carl von Ossietzky Universit(a)t, Institut für Physik and Center of Interface Science, 26129 Oldenbu
论文部分内容阅读
Observing the motion of electrons on their natural nanometer length and femtosecond time scales is a fundamental goal of and an open challenge for contemporary ultrafast science1-5.At present,optical techniques and electron microscopy mostly provide either ultrahigh temporal or spatial resolution,and microscopy techniques with combined space-time resolution require further development6-11.In this study,we create an ultrafast electron source via plasmon nanofocusing on a sharp gold taper and implement this source in an ultrafast point-projection electron microscope.This source is used in an optical pump—electron probe experiment to study ultrafast photoemissions from a nanometer-sized plasmonic antenna12-15.We probe the real space motion of the photoemitted electrons with a 20-nm spatial resolution and a 25-fs time resolution and reveal the deflection of probe electrons by residual holes in the metal.This is a step toward time-resolved microscopy of electronic motion in nanostructures.
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