Superchiral Light Generation on Degenerate Achiral Surfaces

Abraham Vázquez-Guardado and Debashis Chanda

Phys. Rev. Lett. 120, 137601 – Published 28 March 2018

Abstract

A novel route of superchiral near-field generation is demonstrated based on geometrically achiral systems supporting degenerate and spatially superimposed plasmonic modes. Such systems generate a single-handed chiral near field with simultaneous zero far-field circular dichroism. The phenomenon is theoretically elucidated with a rotating dipole model, which predicts a uniform single-handed chiral near field that flips handedness solely by reversing the handedness of the source. This property allows detection of pure background free molecular chirality through near-field light-matter interaction, which is experimentally demonstrated in the precise identification of both handedness of a chiral molecule on a single substrate with about four orders of magnitude enhancement in detection sensitivity compared to its conventional volumetric counterpart.

Received 20 October 2017

DOI:https://doi.org/10.1103/PhysRevLett.120.137601

Physics Subject Headings (PhySH)

Optical microcavities Plasmonics Polarization of light

Atomic, Molecular & Optical

Authors & Affiliations

Abraham Vázquez-Guardado^1,2 and Debashis Chanda^1,2,3,*

¹CREOL, College of Optics and Photonics, University of Central Florida, Orlando, Florida 32816, USA
²NanoScience Technology Center, University of Central Florida, Orlando, Florida 32826, USA
³Department of Physics, University of Central Florida, Orlando, Florida 32816, USA