Variation of optical polarization in reflected light by redistribution of electric charge in metals

In this work, the observation of phase delay changes between parallel and perpendicular components of an optical beam reflected on a metal surface is reported. Those changes have been induced by electrically charging a metal with static charge. A quasimonochromatic lineally polarized beam is directed to a piece of steel where the beam is reflected, the polarization of the reflected beam is in general elliptical. The module of each polarization component and their difference of phase are measured with an ellipsometer. For the experiments we have started by making ellipsometry measurements on a grounded steel sample, then a second measurement has been carried out on the same sample after inducing electrostatic charge, results indicate a rotation of the elliptical polarization in the beam reflected on the electrically charged sample.