title: Towards Terawatt Sub-Cycle Long-Wave Infrared Pulses via Chirped Optical Parametric Amplification and Indirect Pulse Shaping.
abstract: We present an approach for both efficient generation and amplification of 4-12 μm pulses by tailoring the phase matching of the nonlinear crystal Zinc Germanium Phosphide (ZGP) in a narrowband-pumped optical parametric chirped pulse amplifier (OPCPA) and a broadband-pumped dual-chirped optical parametric amplifier (DC-OPA), respectively. Preliminary experimental results are obtained for generating 1.8-4.2 μm super broadband spectra, which can be used to seed both the signal of the OPCPA and the pump of the DC-OPA. The theoretical pump-to-idler conversion efficiency reaches 27% in the DC-OPA pumped by a chirped broadband Cr2+:ZnSe/ZnS laser, enabling the generation of  Terawatt-level 4-12 μm pulses with an available large-aperture ZGP. Furthermore, the 4-12 μm idler pulses can be compressed to sub-cycle pulses by compensating the tailored positive chirp of the idler pulses using the bulk compressor NaCl, and by indirectly controlling the higher-order idler phase through tuning the signal (2.4-4.0 μm) phase with a commercially available acousto-optic programmable dispersive filter (AOPDF). A similar approach is also described for generating high-energy 4-12 μm sub-cycle pulses via OPCPA pumped by a 2 μm Ho:YLF laser.
authors.affiliation: Institute for the Frontier of Attosecond Science and Technology, CREOL and Department of Physics, University of Central Florida, Orlando, Florida, 32816, USA.
authors.forename: Yanchun
authors.initials: Y
authors.lastname: Yin
authors.affiliation: Institute for the Frontier of Attosecond Science and Technology, CREOL and Department of Physics, University of Central Florida, Orlando, Florida, 32816, USA.
authors.forename: Andrew
authors.initials: A
authors.lastname: Chew
authors.affiliation: Institute for the Frontier of Attosecond Science and Technology, CREOL and Department of Physics, University of Central Florida, Orlando, Florida, 32816, USA.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Ren
authors.affiliation: Institute for the Frontier of Attosecond Science and Technology, CREOL and Department of Physics, University of Central Florida, Orlando, Florida, 32816, USA.
authors.forename: Jie
authors.initials: J
authors.lastname: Li
authors.affiliation: Institute for the Frontier of Attosecond Science and Technology, CREOL and Department of Physics, University of Central Florida, Orlando, Florida, 32816, USA.
authors.forename: Yang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Institute for the Frontier of Attosecond Science and Technology, CREOL and Department of Physics, University of Central Florida, Orlando, Florida, 32816, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Institute for the Frontier of Attosecond Science and Technology, CREOL and Department of Physics, University of Central Florida, Orlando, Florida, 32816, USA.
authors.forename: Zenghu
authors.initials: Z
authors.lastname: Chang