Induced optical chirality and circularly polarized emission from achiral CdSe/ZnS quantum dots via resonantly coupling with plasmonic chiral metasurfaces

Abstract

Functionalization of quantum dots to induce circular dichroism as well as the direct emission of circularly polarized light is the subject of intensive studies for the obvious importance not only in practical applications but also in gaining a deeper understanding of quantum semiconductor heterostructures. In this work, remarkable chiral features in achiral CdSe/ZnS colloidal quantum dots (CQDs) induced by plasmonic chiral metasurfaces are reported. Not only giant circular dichroism, but also a high degree of circular polarization in the light emitted by the CQDs hybridized with the chiral metasurfaces is observed. By probing the response of CQDs combined with tunable chiral metasurfaces, it is shown that the induced chiral features are closely linked to the correlation between the absorption bands of CQDs and the chiral bands of the metasurfaces. The findings indicate that plasmonic chiral metasurface is an effective medium in reshaping CQDs with useful chiral properties.