We present experimental and numerical investigations of high-energy mid-infrared filamentation with multi-octavespanning supercontinuum generation(SCG), pumped by a 2.4 μm, 250 fs Cr:ZnSe chirped-pulse laser amplifie...We present experimental and numerical investigations of high-energy mid-infrared filamentation with multi-octavespanning supercontinuum generation(SCG), pumped by a 2.4 μm, 250 fs Cr:ZnSe chirped-pulse laser amplifier.The SCG is demonstrated in both anomalous and normal dispersion regimes with YAG and polycrystalline ZnSe,respectively. The formation of stable and robust single filaments along with the visible-to-mid-infrared SCG is obtained with a pump energy of up to 100 μJ in a 6-mm-long YAG medium. To the best of the authors’ knowledge, this is the highest-energy multi-octave-spanning SCG from a laser filament in a solid. On the other hand, the SCG and evenharmonic generation based on random quasi-phase matching(RQPM) are simultaneously observed from the single filaments in a 6-mm-long polycrystalline ZnSe medium with a pump energy of up to 15 μJ. The numerical simulations based on unidirectional pulse propagation equation and RQPM show excellent agreement with the measured multioctave-spanning SCG and even-harmonic generation. They also reveal the temporal structure of mid-infrared filaments,such as soliton-like self-compression in YAG and pulse broadening in ZnSe.展开更多
基金supported by the US DOE accelerator stewardship program(grant number DE-SC0018378)US DOD Office of Navy Research(ONR)DURIP(grant number N00014-17-1-2744)+5 种基金National Science Foundation(NSF)(grant number PHY-1707237)Air Force Office of Scientific Research(AFOSR)(grant number FA9550-18-1-0223)Integrated Electronics Engineering Center(IEEC)of Binghamton UniversityERDF and the state budget(grant number CZ.02.1.01/0.0/0.0/15006/0000674)MEYS(grant number LO1602,LM2015086)of the Czech RepublicEU Horizon 2020(grant number 739573)。
文摘We present experimental and numerical investigations of high-energy mid-infrared filamentation with multi-octavespanning supercontinuum generation(SCG), pumped by a 2.4 μm, 250 fs Cr:ZnSe chirped-pulse laser amplifier.The SCG is demonstrated in both anomalous and normal dispersion regimes with YAG and polycrystalline ZnSe,respectively. The formation of stable and robust single filaments along with the visible-to-mid-infrared SCG is obtained with a pump energy of up to 100 μJ in a 6-mm-long YAG medium. To the best of the authors’ knowledge, this is the highest-energy multi-octave-spanning SCG from a laser filament in a solid. On the other hand, the SCG and evenharmonic generation based on random quasi-phase matching(RQPM) are simultaneously observed from the single filaments in a 6-mm-long polycrystalline ZnSe medium with a pump energy of up to 15 μJ. The numerical simulations based on unidirectional pulse propagation equation and RQPM show excellent agreement with the measured multioctave-spanning SCG and even-harmonic generation. They also reveal the temporal structure of mid-infrared filaments,such as soliton-like self-compression in YAG and pulse broadening in ZnSe.