3.2-mJ, 92-fs pulses centered at 3.1 µm are generated at a 1-kHz repetition rate through a tabletop optical parametric chirped pulse amplification (OPCPA) system based on ZnGeP2crystals. Pumped by a 2-µm chirped pulse amplifier with a flat-top beam profile, the amplifier achieves a 16.5% overall efficiency, which, to the best of our knowledge, is the highest efficiency achieved by OPCPA at this wavelength. Harmonics up to the seventh order are observed after focusing the output in the air. 
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                            Few-cycle, mJ-level, mid-wave infrared pulses generated via post-compression of a chirped pulse amplifier
                        
                    
    
            Few-cycle pulses were generated by passing a beam from a cryogenically cooled Fe:ZnSe chirped-pulse amplifier (CPA) at a repetition rate of 400 Hz through a gas-filled hollow core fiber (HCF) followed by dispersion-compensating bulk CaF2. The krypton-filled fiber at 370 kPa yielded 1.14-mJ, 42-fs pulses centered at 4.07 µm, while the oxygen-filled fiber at 310 kPa delivered 0.78-mJ, 39-fs pulses spanning from 3 to 5.5 µm. This work is a step toward a high repetition rate mid-wave infrared driver of isolated attosecond keV x-ray pulses. 
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                            - Award ID(s):
- 2207674
- PAR ID:
- 10610448
- Publisher / Repository:
- Optica
- Date Published:
- Journal Name:
- Optics Letters
- Volume:
- 49
- Issue:
- 11
- ISSN:
- 0146-9592
- Page Range / eLocation ID:
- 3170
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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