Cascaded Generation of a Sub-10-Attosecond Half-Cycle Pulse

TL;DR

This paper introduces a novel plasma-based cascade method to generate isolated sub-10-attosecond half-cycle pulses, enabling advanced electron manipulation at atomic timescales.

Contribution

It presents a new plasma cascade technique for producing ultra-short half-cycle pulses, achievable with existing laser technology and plasma shaping.

Findings

Simulations show 8.3-attosecond pulses can be generated.

The method works with both one-cycle and shaped multi-cycle lasers.

Potential for practical implementation with commercial lasers.

Abstract

Sub-10-attosecond pulses with half-cycle electric fields provide exceptional options to detect and manipulate electrons in the atomic timescale. However, the availability of such pulses is still challenging. Here, we propose a method to generate isolated sub-10-attosecond half-cycle pulses based on a cascade process naturally happening in plasma. A 100s-attosecond pulse is first generated by shooting a moderate overdense plasma with a one-cycle femtosecond pulse. After that, the generated attosecond pulse cascadedly produce a sub-10-attosecond half-cycle pulse in the transmission direction by unipolarly perturbing a nanometer-thin relativistic electron sheet naturally form in the plasma. Two-dimensional particle-in-cell simulations indicate that an isolated half-cycle pulse with the duration of 8.3 attoseconds can be produced. Apart from one-cycle driving pulse, such a scheme also can be realized with a commercial 100-TW 25-fs driving laser by shaping the pulse with a relativistic plasma lens in advance.