Nonlinear Interaction of Polarization Singular Beams

摘要

Polarization singularities are points at which any of the parameters that define the state of polarization becomes undefined in an inhomogeneous polarized field. Second harmonic generation (SHG) of both vector and ellipse field polarization singularities is studied. The transformation of these singular points under SHG for propagation parallel to the optic axis is studied. The topological charge of the V-point singularities and C-point singularities are predicted to be doubled and the sign is getting reversed in the non-linear medium. L-lines are stable, and no new L-lines are formed for ellipse fields. These results are verified for all the four types of V-point singularities and right and left handed positive and negative C-points.