Centre for Hypersonics, The University of Queensland, Brisbane, QLD 4072, Australia.
Opt Lett. 2013 Mar 1;38(5):664-6. doi: 10.1364/OL.38.000664.
Laser-induced plasmas in gases are known to generate gaseous jets in the postplasma gas plume. The gaseous jet typically develops toward the laser source, and the experiments presented here show, for the first time to our knowledge, that, under certain conditions, these jets can develop in the opposite direction or may not form at all. The data suggest that this is related to the ratio between the energy absorbed in the plasma and the threshold breakdown energy, effectively leading to multiple plasma initiation sites in the focal waist.
众所周知，激光在气体中产生的等离子体会在等离子体羽流中产生气体射流。气体射流通常朝着激光源发展，但这里展示的实验首次表明，在某些条件下，这些射流可能会朝相反的方向发展，或者根本不会形成。这些数据表明，这与等离子体中吸收的能量与击穿阈值能量的比值有关，这有效地导致在焦点腰部产生多个等离子体起始点。
