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 e...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.展开更多
基金the Deutsche Forschungsgemeinschaft for support within the priority program QUTIF(SPP1840)support from SPP1839,the German-Israeli Foundation(GIF grant no.1256)+2 种基金the Korea Foundation for International Cooperation of Science and Technology(Global Research Laboratory project,K20815000003)is acknowledgedthe HPC Cluster CARL in Oldenburg(DFG INST 184/157-1 FUGG)the Studienstiftung des Deutschen Volkes for the personal grant.
文摘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.
