We investigated the filamentation in air of 7 ps laser pulses of up to 200 mJ energy from a 1.03 μm-wavelength Yb:YAG laser at repetition rates up to
We experimentally demonstrate long-wavelength-infrared (LWIR) femtosecond filamentation in solids. Systematic investigations of supercontinuum (SC) generation and self-compression of the LWIR pulses assisted by laser filamentation are performed in bulk KrS-5 and ZnSe, pumped by
- Award ID(s):
- 1707237
- NSF-PAR ID:
- 10143155
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Letters
- Volume:
- 45
- Issue:
- 8
- ISSN:
- 0146-9592; OPLEDP
- Page Range / eLocation ID:
- Article No. 2175
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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. Interferograms of the wake generated show that while pulses in a train of repetition rate encounter a nearly unperturbed environment, at , a channel with an axial air density hole of is generated and maintained at all times by the cumulative effect of preceding laser pulses. Measurements at show that the energy deposited decreases proportional to the air channel density depletion, becoming more pronounced as the repetition rate and pulse energy increase. Numerical simulations indicate that contrary to filaments generated by shorter duration pulses, the electron avalanche is the dominant energy loss mechanism during filamentation with 7 ps pulses. The results are of interest for the atmospheric propagation of joule-level picosecond pulses from Yb:YAG lasers, of which average powers now surpass 1 kW, and for channeling other directed energy beams. -
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