Ellipsometry of biological objects in the mode of attenuated total reflection (ATR) using a circularly polarized laser light

摘要

The paper discusses the use of a laser wave of elliptical and circular polarization under ATR conditions. It is shown that when a wave of right circular polarization is incident on an object under study, a change in the nature of polarization occurs when scanning the angle of incidence - from the right elliptical, through the linear to the left elliptical. The analysis of the parameters of the ellipse and ellipsometric parameters during the incidence of a circularly polarized wave on a layered prism-metal-air and prism-metal-bioobject-air structure according to the Kretschman scheme under the condition of excitation of surface plasmons is carried out. For the first time, the characteristic shifts between the minima of the eliipsometric parameters and the parameters of the ellipse of polarization of reflected light, carrying information about the object under study, were calculated. It is also shown for the first time that for these parameters the maxima of the ellipsometry parameter and the ellipse parameter shift, which is responsible for the eccentricity and direction of rotation of the field vector along the polarization ellipse. The results obtained expand the scope of plasmon resonance spectroscopy to the more general case of elliptically polarized light.