Optical Control of Young's Type Double-slit Interferometer for Laser-induced Electron Emission from a Nano-tip

TL;DR

This paper demonstrates an optical method to control a double-slit electron interferometer at a nano-tip, enabling interference observation previously hindered by large slit separation, advancing electron holography techniques.

Contribution

It introduces an optically controlled double-slit setup at a nano-tip, allowing dynamic adjustment of slit parameters for electron interference experiments.

Findings

Achieved interference between two electron waves from a nano-tip apex.

Controlled slit separation and opening using laser pulse intensity and polarization.

Paves the way for time-resolved electron holography on molecules.

Abstract

Interference experiments with electrons in a vacuum can illuminate both the quantum and the nanoscale nature of the underlying physics. An interference experiment requires two coherent waves, which can be generated by splitting a single coherent wave using a double slit. If the slit-edge separation is larger than the coherence width at the slit, no interference appears. Here we employed variations in surface barrier at the apex of a tungsten nano-tip as slits and achieved an optically controlled double slit, where the separation and opening-and-closing of the two slits can be controlled by respectively adjusting the intensity and polarization of ultrashort laser pulses. Using this technique, we have demonstrated interference between two electron waves emitted from the tip apex, where interference has never been observed prior to this technique because of the large slit-edge separation. Our findings pave the way towards simple time-resolved electron holography on e.g. molecular adsorbates employing just a nano-tip and a screen.