The practical applications of chiral discrimination are usually limited by the weak chiral response of enantiomers and the high complexity of detection methods. Here, we propose to use the C lines (i.e., lines of polarization singularities) emerged in light scattering by a metal sphere to detect the chirality of small chiral particles. Using full-wave numerical simulations and analytical multipole expansions, we determined the absorption dissymmetry of the chiral particles at different positions on the C lines and found that it can be much larger than that induced by circularly polarized plane wave excitation. We uncover that the large dissymmetry factor is attributed to the asymmetric absorption of electric and magnetic dipoles induced by the C lines. The results can generate novel methods of chiral discrimination and may find applications in optical manipulations, optical sensing, and chiral quantum optics.
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