Generation of Intense Deep-Ultraviolet Pulses at 200 nm

TL;DR

This paper demonstrates a method to generate intense, ultrashort deep ultraviolet pulses at 200 nm with high energy, using cascaded sum frequency generation in barium borate crystals, advancing ultrafast spectroscopy capabilities.

Contribution

The authors present a novel approach for efficient generation of high-energy, ultrashort deep UV pulses at 200 nm through optimized phase-matching and dispersion control in nonlinear crystals.

Findings

Generated 48 fs pulses at 200 nm with 130 μJ energy.

Achieved efficient frequency up-conversion in barium borate crystals.

Provided detailed temporal and phase characterization of the pulses.

Abstract

We report the generation of intense deep ultraviolet pulses at 200 nm with a duration of 48 fs and pulse energy of 130 uJ, achieved via cascaded sum frequency generation using 800 nm femtosecond pulses in barium borate crystals. Efficient frequency up-conversion is realized by optimizing phase-matching conditions and implementing dispersion control, while maintaining the ultrashort pulse characteristics. The generated deep ultraviolet pulses are characterized using two-photon absorption frequency-resolved optical gating, providing detailed insight into their temporal profile and phase. This approach addresses key challenges in ultrashort deep ultraviolet pulse generation, delivering a high-energy, ultrashort source suitable for ultrafast spectroscopy, nonlinear optics, and strong-field physics. These results represent a significant advancement in the generation of high-energy, ultrashort deep ultraviolet pulses, opening new possibilities for time-resolved investigations in ultrafast molecular dynamics, as well as emerging applications in semiconductor science, quantum materials, and photochemistry.