High Flux Isolated Attosecond XUV Source
Abstract
Time-resolved experiments with attosecond resolution have been performed thus far by combining weak extreme ultraviolet (XUV) pulses with stronger near infrared (NIR) lasers. Isolated attosecond pulses with high photon flux are required to perform attosecond pump Ð attosecond probe experiments. In order to scale up the isolated attosecond pulse energy, we have developed a Ti:Sapphire laser system optimized to provide both high-energy (350 mJ) and short-duration (13.9 fs) pulses for implementing Generalized Double Optical Gating (GDOG). With this laser, an extreme ultraviolet (XUV) super-continuum supporting 230 as isolated attosecond pulses at 35 eV was generated using the GDOG technique. The XUV pulse energy reached 100 nJ. Direct carrier-envelope phase (CEP) locking is not feasible since the driving laser is operating at a repetition rate of 10 Hz, which is too slow for the sampling and active feedback. Without CEP stabilization, the GDOG technique ensures isolated attosecond pulses can be generated by every shot of the driving laser, but the CEP fluctuations alter the energy of each pulse. A scheme for stabilizing the carrier-envelope phase of low-repetition rate lasers was demonstrated for the first time. The influence of the CEP on the generation of a quasi-continuum in the extreme ultraviolet was observed.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jun 25, 2021
- Source ID
- W911NF1210456
Entities
People
- Zenghu Chang
Organizations
- Army Contracting Command
- United States Army
- University of Central Florida