Superchiral electromagnetic fields created by surface plasmons in nonchiral metallic nanostructures
TJ Davis, E Hendry
Physical Review B | AMER PHYSICAL SOC | Published : 2013
We show theoretically that localized surface plasmons can generate optical fields with a chirality exceeding that of circularly polarized light by a factor of 50. This superchiral optical field can be formed from linearly polarized light incident on nonchiral metal structures. We identify three mechanisms that lead to large optical chirality involving the coupling between the incident light and the evanescent fields of the surface plasmons. Two of these mechanisms create superchiral regions with nonzero average chirality suitable for the excitation of chiral molecules in solution. © 2013 American Physical Society.
Awarded by Engineering and Physical Sciences Research Council