4 papers
Optical vortex coronagraph imaging of a laser-induced plasma filament
Qingqing Liang, Xia Huang, Yanfei Mou +7
A high contrast imaging technique based on an optical vortex coronagraph (OVC) is used to measure the spatial phase profile induced by an air plasma generated by a femtosecond lase…
Coherent control of superradiance from nitrogen ions pumped with femtosecond pulses
An Zhang, Qingqing Liang, Mingwei Lei +8
Singly ionized nitrogen molecules in ambient air pumped by near-infrared femtosecond laser give rise to superradiant emission. Here we demonstrate coherent control of this superrad…
Lasing without population inversion in air
André Mysyrowicz, Rostyslav Danylo, Pengji Ding +8
A cavity-free laser in the sky could lead to revolutionary improvements in optical remote sensing for atmospheric science. Abundant in air, nitrogen molecules are prime candidates…
Backward lasing of singly ionized nitrogen ions pumped by femtosecond laser pulses
Xiang Zhang, Rostyslav Danylo, Zhengquan Fan +6
We report on the observation of backward lasing at 391.4 nm of nitrogen ions pumped by linearly polarized intense femtosecond pulses at 800 nm. The strongly enhanced spectral inten…