High Harmonic Generation with Twisted Electrons

TL;DR

This paper investigates high harmonic generation using twisted electrons, revealing how their orbital angular momentum influences the polarization and spectrum of emitted attosecond pulses through analytical and numerical methods.

Contribution

It introduces a detailed analysis of high harmonic emission from twisted electrons, highlighting the effects of collision geometry on polarization and spectral properties.

Findings

Circularly polarized attosecond pulses can be generated from twisted electrons.

The polarization of emitted harmonics depends on the impact parameter of collisions.

A transition from circular to linear polarization occurs with increasing impact parameter.

Abstract

We present analytically and numerically the spectrum of high harmonic emission generated by twisted electrons in the presence of linearly polarized light. Ensuing transitions from electronic continuum states with orbital angular momentum to bound states give rise to circularly polarized attosecond pulses. For central collisions with twisted wavepackets continuum-bound transitions are subject to dipole selection rules. For non-central collisions a crossover from circularly to linearly polarized emission occurs for increasing impact parameter, due to the transverse topology of twisted wavepackets.