Plasmonic lenses for tunable ultrafast electron emitters at the nanoscale

Abstract

Simultaneous spatio-temporal confinement of energetic electron pulses to femtosecond and nanometer scales is a topic of great interest in the scientific community, given the potential impact of such development on a wide spectrum of scientific and industrial applications. For example, in ultrafast electron scattering, nanoscale probes would enable accurate maps of structural dynamics in materials with nanoscale heterogeneity, thereby understanding the role of boundaries and defects on macroscopic properties. On the other hand, advances in this field are mostly limited by the electron source brightness and size. We present the design, fabrication, and optical characterization of bullseye plasmonic lenses for next-generation ultrafast electron sources. Using electromagnetic simulations, we examine how the interplay between light-plasmon coupling, plasmon propagation, dispersion, and resonance governs the properties of the photoemitted electron pulse. We also illustrate how the pulse duration and strength can be tuned by geometric design, and predict sub-10 fs pulses with nanoscale diameter can be achieved. We then fabricated lenses in gold films and characterized their plasmonic properties with cathodoluminescence spectromicroscopy, demonstrating suitable plasmonic behavior for ultrafast, nanoscale photoemission.

References in corpus (10)

• Optical excitations in electron microscopy
• Plasmonic Films Can Easily Be Better: Rules and Recipes
• Dielectric Laser Acceleration
• Carrier-envelope phase effects on the strong-field photoemission of electrons from metallic nanostructures
• Direct measurement of sub-10 fs relativistic electron beams with ultralow emittance
• Angle-resolved cathodoluminescence spectroscopy
• Angle-resolved cathodoluminescence imaging polarimetry
• Terahertz streaking of few-femtosecond relativistic electron beams
• Nanoscale mapping of ultrafast magnetization dynamics with femtosecond Lorentz microscopy
• Nanoscale diffractive probing of strain dynamics in ultrafast transmission electron microscopy

Cited by in corpus (2)

• Relativistic ultrafast electron diffraction at high repetition rates
• Ultrafast Electron Diffraction: Visualizing Dynamic States of Matter