Attosecond Field Emission

TL;DR

This paper demonstrates real-time probing of electron emission dynamics at the attosecond scale using intense optical transients, revealing ultrafast emission profiles and near-field interactions at the nanoscale.

Contribution

It introduces a method to directly measure and control attosecond electron emission from nanotips using sub-cycle optical transients.

Findings

Electron pulses with a duration of 53 attoseconds were generated.

Real-time measurement of emission chirp was achieved.

Nanoscale near-fields were directly probed.

Abstract

Field-emission of electrons underlies major advances in science and technology, ranging from imaging the atomic-scale structure of matter to signal processing at ever-higher frequencies. The advancement of these applications to their ultimate limits of temporal resolution and frequency calls for techniques that can confine and probe the field emission on the sub-femtosecond time scale. We used intense, sub-cycle transients to induce optical field emission of electron pulses from tungsten nanotips and a weak replica of the same transient to directly probe the emission dynamics in real-time. Access into the temporal profile of the emerging electron pulses, including the duration $\tau$ = (53 as $\pm$ 5 as) and chirp, and the direct probing of nanoscale near-fields, open new prospects for research and applications at the interface of attosecond physics and nanooptics.