Ultrafast time resolved photo-electric emission

TL;DR

This paper demonstrates ultrafast measurement of electron emission times from a tungsten tip using laser excitation and microwave cavities, achieving femtosecond resolution and enabling precise phase measurements.

Contribution

It introduces a novel technique for directly characterizing electron emission delays with femtosecond precision under near-infrared laser excitation.

Findings

Emission delays up to 10 fs observed.

Timing resolution of ~ fs achieved.

Microwave phase measured with <70 fs precision.

Abstract

The emission times of laser-triggered electrons from a sharp tungsten tip are directly characterized under ultrafast, near-infrared laser excitation at Keldysh parameters $6.6< \gamma < 19.1$. Emission delays up to 10 fs are observed, which are inferred from the energy gain of photoelectrons emitted into a synchronously driven microwave cavity. ~ fs timing resolution is achieved in a configuration capable of measuring timing shifts up to 55 ps. The technique can also be used to measure the microwave phase inside the cavity with a precision below 70 fs upon the energy resolved detection of a single electron.