Interference-contrast optical activity: a new technique for probing the chirality of anisotropic samples and more

R P Cameron; U Vogl; N Trautmann

doi:10.1098/rsos.192201

Interference-contrast optical activity: a new technique for probing the chirality of anisotropic samples and more

R Soc Open Sci. 2020 May 13;7(5):192201. doi: 10.1098/rsos.192201. eCollection 2020 May.

Authors

R P Cameron¹, U Vogl², N Trautmann²

Affiliations

¹ SUPA and Department of Physics, University of Strathclyde, Glasgow, G4 0NG, UK.
² Corporate Research and Technology, Carl Zeiss AG, Carl-Zeiss-Strasse 22, Oberkochen 73447, Germany.

Abstract

We introduce interference-contrast optical activity (ICOA) as a new technique for probing the chirality of anisotropic samples and more. ICOA could underpin a new class of 'chiral microscopes', with potential applications spanning the range of chirality and beyond. Two possible versions of ICOA are described explicitly; one designed to probe the optical rotation of a transparent sample regardless of the sample's linear birefringence (ICOA-OR) and another designed to probe gradients in the optical rotation of a transparent sample (ICOA-GOR). Simulated results for α-quartz lead us to suggest that ICOA-GOR might be applied to help monitor the growth of chiral crystals in the pharmaceutical industry. Possible directions for future research are highlighted.

Keywords: DIC; chirality; microscopy; optical activity; polarimetry; polarization.