Fraunhofer-type absorption line splitting and polarization in confocal double-pulse laser induced plasma

Strong line splitting and polarization are observed in Fraunhofer-type absorption lines in Pb, Sn, Si, Cd, In, and Zn in confocal double-pulse laser induced plasma (DP-LIP) experiments. This effect is detectable using medium laser power densities: (similar to 1-2) x 10(13) W/m(2) for the first laser pulse and 1 x 10(14) W/m(2) for the second laser pulse. Polarization and splitting effects exist only during the second laser pulse (similar to 7 ns). Absorption line polarization and splitting phenomena may be explained by a high overall magnetic field and motional Stark effect caused by the second laser pulse inside the laser plasma created by the first pulse. (C) 2013 Elsevier B.V. All rights reserved.