Abstract

Light-induced drift (LID) of atoms and molecules arises from a combination of two effects. One one them is the electronic or vibrational velocity-selective excitation of species due to the Doppler effect. The other one is the difference in velocity changing collisional cross-sections (friction of the flow) of excited and ground-state particles with a buffer gas. Unlike the effects based on light pressure, LID does not require momentum transfer from photons to particles, since the two counter-propagating flows of the absorbing and buffer gas, one through the other, compensate each other. LID was originally proposed for excitation with monochromatic laser radiation.^[1]

© 1992 IQEC