Circular dichroism induced by Fano resonances in planar chiral oligomers. Issue 1 (16th November 2015)

• Record Type: Journal Article
• Authors: Hopkins, Ben; Poddubny, Alexander N.; Miroshnichenko, Andrey E.; Kivshar, Yuri S.
• Is Part Of: Laser & photonics reviews. Volume 10:Issue 1(2016:Jan.)
• Page Start: 137
• Page End: 146
• Publication Date: 2015-11-16
• Subjects: Fano resonance -- Circular dichroism -- Planar chirality -- Nanoparticle oligomer; Lasers -- Periodicals; Photonics -- Periodicals; Lasers -- Périodiques; Photonique -- Périodiques; 621.36
• DOI: 10.1002/lpor.201500222
• Languages: English
• ISSNs: 1863-8880

Abstract

Abstract : The energy imparted by circularly polarized light on chiral matter is known to depend on the handedness of light; an effect known as a circular dichroism. This study reveals that an analogous effect can be realized in two‐dimensional, planar chiral, nanostructures through a form of circular dichroism in far‐field radiation and near‐field material absorption that originates from Fano‐like modal interference. Abstract: We present a general theory of circular dichroism in planar chiral nanostructures with rotational symmetry. It is demonstrated, analytically, that the handedness of the incident field's polarization can control whether a nanostructure induces either absorption or scattering losses, even when the total optical loss (extinction) is polarization‐independent. We show that this effect is a consequence of modal interference so that strong circular dichroism in absorption and scattering can be engineered by combining Fano resonances with planar chiral nanoparticle clusters.