title: Polychromatic polarization singularities.
abstract: Elliptical polarization can appear in only monochromatic optical fields. In polychromatic vector fields the polarization is a Lissajous figure, but in only commensurate fields do the figures have well-defined shapes; in other fields the shapes are undefined. Nonetheless, I show that a given paraxial polychromatic vector field has a coherency ellipse field associated with it that contains polarization singularities and stationary points that are surrogates for the corresponding critical points of the parent optical field.
authors.affiliation: Department of Physics, Bar-Ilan University, Ramat-Gan 52900, Israel. freund@mail.biu.ac.il
authors.forename: Isaac
authors.initials: I
authors.lastname: Freund