2018/03/11 by Xiang Zhang, Zhang, Xiang, Rostyslav Danylo +15
Engineering · Physics and Astronomy · #Advanced Fiber Laser Technologies #FOS: Physical sciences #Laser Design and Applications #Laser-Matter Interactions and Applications #Optics (physics.optics)
paper · pdf · doi:10.48550/arxiv.1803.03968
openalex publication_date 2018/03/11 · openalex created_date 2018/03/29 · openalex updated_date 2026/07/28
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 intensity at 391.4 nm, as well as the amplification of an externally injected backward seeding pulse, confirm that the backward 391.4 nm signal is due to optical amplification in the gas plasma. Compared to the forward emission at 391.4 nm, the optimal backward emission is achieved at a lower gas pressure around 10 mbar, which is due to asymmetry of the backward and forward directions rooted in the traveling excitation geometry. This method, using the widely available 800 nm femtosecond pulses as a pump laser, provides a promising scheme for the generation of backward air laser, which holds a unique potential for optical remote sensing.