Infrared attosecond field transients and UV to IR few-femtosecond pulses generated by high-energy soliton self-compression

TL;DR

This paper demonstrates the generation of attosecond infrared field transients and tunable few-femtosecond pulses across UV to IR wavelengths using high-energy soliton self-compression in hollow capillary fibers, expanding ultrafast science capabilities.

Contribution

It introduces a novel method for soliton self-compression of 1800 nm pulses to sub-cycle durations and generates tunable few-femtosecond pulses from UV to IR with high efficiency.

Findings

Achieved 2 fs pulse duration at 1800 nm with 27 GW peak power.

Generated tunable pulses from 300 nm to 740 nm with up to 25 μJ energy.

Demonstrated a compact second stage producing multi-μJ pulses from 210 nm to 700 nm.

Abstract

Infrared femtosecond laser pulses are important tools both in strong-field physics, driving X-ray high-harmonic generation, and as the basis for widely tuneable, if inefficient, ultrafast sources in the visible and ultraviolet. Although anomalous material dispersion simplifies compression to few-cycle pulses, attosecond pulses in the infrared have remained out of reach. We demonstrate soliton self-compression of 1800 nm laser pulses in hollow capillary fibers to sub-cycle envelope duration (2 fs) with 27 GW peak power, corresponding to attosecond field transients. In the same system, we generate wavelength-tuneable few-femtosecond pulses from the ultraviolet (300 nm) to the infrared (740 nm) with energy up to 25 $\mu$J and efficiency up to 12 %, and experimentally characterize the generation dynamics in the time-frequency domain. A compact second stage generates multi-$\mu$J pulses from 210 nm to 700 nm using less than 200 $\mu$J of input energy. Our results significantly expand the toolkit available to ultrafast science.