Dissociative ionization of ethanol by circularly-polarized ultrashort intense laser fields

高強度・短パルス・円偏光レーザー場によるエタノールの解離性イオン化

赤木 浩; 板倉 隆二; 穂坂 綱一*; 山内 薫; 横山 淳

Akagi, Hiroshi; Itakura, Ryuji; Hosaka, Koichi*; Yamanouchi, Kaoru; Yokoyama, Atsushi

高強度・短パルスレーザー照射によって進行するエタノール分子のイオン化とその後の解離過程を明らかにするために、電子とイオンを3次元運動量を分解したうえで同時計測した。円偏光で測定した電子と解離イオンの角度相関を、直線偏光での測定結果と比較する。

When a molecule is exposed to circularly-polarized laser fields, dissociation processes following ionization proceed differently from the case of linearly polarization. In the present work, ethanol molecules are irradiated with a circularly-polarized intense laser field (I = 1.410 W/cm, 800 nm), and the produced electron and ion are measured in coincidence. Under the present experimental conditions, Keldysh parameter is calculated to be 2.6, suggesting the multiphoton ionization is expected to be dominant. The relative yields of CHOH, CHOH, and CHC with respect to the parent ion are 0.36, 0.31, and 0.01, which correspond to only 0.5, 0.4, and 0.2 of those for the linear polarization with similar laser field intensity (1.710 W/cm.