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While industrial-grade Yb-based amplifiers have become very prevalent, their limited gain bandwidth has created a large demand for robust spectral broadening techniques that allow for few-cycle pulse compression. In this work, we perform a comparative study between several atomic and molecular gases as media for spectral broadening in a hollow-core fiber geometry. Exploiting nonlinearities such as self-phase modulation, self-steepening, and stimulated Raman scattering, we explore the extent of spectral broadening and its dependence on gas pressure, the critical power for self-focusing, and the optimal regime for few-cycle pulse compression. Using a 3-mJ, 200-fs input laser pulses, we achieve 17 fs, few-cycle pulses with 80% fiber energy transmission efficiency. The optimal parameters can be scaled for higher or lower input pulse energies with appropriate gas parameters and fiber geometry.
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Acousto-optic modulator pulse-shaper compression of octave-spanning pulses from a stretched hollow-core fiber
We demonstrate spectral broadening and compression of amplified pulses from a titanium sapphire laser system using an argon-filled stretched, hollow-core fiber and an acousto-optic modulator based pulse-shaper. We characterize the pulses using pulse-shaper assisted collinear frequency resolved optical gating, pulse-shaper assisted D-scans, and D-scans using a variable path length water cell. The different compression and characterization approaches consistently compress the pulses down to < 6 fs, less than ∼1 fs from the transform limit. We discuss prospects for pulse shape spectroscopy with these broadband pulses, given our control over the spectral amplitude and phase.
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- Award ID(s):
- 2110376
- PAR ID:
- 10531126
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- OSA Continuum
- Volume:
- 4
- Issue:
- 12
- ISSN:
- 2578-7519
- Format(s):
- Medium: X Size: Article No. 3176
- Size(s):
- Article No. 3176
- Sponsoring Org:
- National Science Foundation
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