Measuring polarizability anisotropies of rare gas diatomic molecules by laser-induced molecular alignment technique

摘要

The polarizability anisotropies of homonuclear rare gas diatomic molecules, Ar2, Kr2, and Xe2, are investigated by utilizing the interaction of the induced electric dipole moment with a nonresonant, nanosecond laser pulse. The degree of alignment, which depends on the depth of the interaction potential created by the intense laser field, is measured, and is found to increase in order of Ar2, Kr2, and Xe2 at the same peak intensity. Compared with a reference I2 molecule, Ar2, Kr2, and Xe2 are found to have the polarizability anisotropies of 0.45 ± 0.13, 0.72 ± 0.13, and 1.23 ± 0.21 Å3, respectively, where the uncertainties (one standard deviation) in the polarizability anisotropies are carefully evaluated on the basis of the laser intensity dependence of the degree of alignment. The obtained values are compared with recent theoretical calculations and are found to agree well within the experimental uncertainties. © 2011 American Institute of Physics Article Outline INTRODUCTION EXPERIMENTAL RESULTS Preparation of rare gas diatomic molecules Abel-inverted images of Xe 2 Evaluation of the degree of alignment Kinetic energy and angular distributions of Kr 2 and Ar 2 DISCUSSIONS The degree of alignment of reference I 2 molecules Polarizability anisotropy of Xe 2 molecules Polarizability anisotropies of Kr 2 and Ar 2 molecules CONCLUSION