Generation of attosecond soft x-ray pulses in a longitudinal space charge amplifier

TL;DR

This paper proposes using a longitudinal space charge amplifier (LSCA) in the soft x-ray regime to generate extremely short attosecond pulses with high peak power and contrast, enhancing free electron laser capabilities.

Contribution

It introduces a novel application of LSCA for attosecond pulse generation in the soft x-ray regime, demonstrating feasibility with a compact setup.

Findings

Generation of 60 attosecond x-ray pulses with 100 MW peak power

Achieved contrast above 98% in pulse generation

Potential integration with existing FEL facilities like FLASH

Abstract

A longitudinal space charge amplifier (LSCA), operating in soft x-ray regime, was recently proposed. Such an amplifier consists of a few amplification cascades (focusing channel and chicane) and a short radiator undulator in the end. Broadband nature of LSCA supports generation of few-cycle pulses as well as wavelength compression. In this paper we consider an application of these properties of LSCA for generation of attosecond x-ray pulses. It is shown that a compact and cheap addition to the soft x-ray free electron laser facility FLASH would allow to generate 60 attosecond (FWHM) long x-ray pulses with the peak power at 100 MW level and a contrast above 98%.