Harmonic concatenation of 1.5-femtosecond-pulses in the deep ultraviolet

TL;DR

This paper demonstrates a novel method to generate 1.5 femtosecond pulses in the deep ultraviolet region by concatenating spatial and temporal harmonics produced by two noncollinear IR-VIS pulses in MgF2.

Contribution

It introduces a new technique for synthesizing ultrashort deep UV pulses using harmonic concatenation controlled by groove-envelope phase.

Findings

Successful generation of 1.5 fs deep UV pulses.

Control of pulse duration via groove-envelope phase.

Extension of ultrashort pulse generation into the deep UV region.

Abstract

Laser pulses with a duration of one femtosecond or shorter can be generated both in the IR-VIS and in the extreme UV, but the deep UV is a spectral region where such extremely short pulses have not yet been demonstrated. Here, a method for the synthesis of ultrashort pulses in the deep UV is demonstrated, which utilizes the temporal and spatial harmonics that are generated by two noncollinear IR-VIS pulses in a thin MgF2 plate. By controlling the groove-envelope phase of the IR-VIS pulses, spatial harmonics are concatenated to form deep UV waveforms with a duration of 1.5 fs.