Chirality is a fundamental property of the universe that determines the active structure of the molecules of life and their behavior, as well as, the fundamental interactions of elementary particles. Chiral sensing and analysis is thus of paramount importance to many scientific fields, with applications ranging from the study of biological processes, the design and synthesis of new drugs, to tests of fundamental symmetries of the universe.
The limited application of chiral sensing in different scientific fields originates from the fact that chiral signals are typically very weak. Traditional optical methods for chiral sensing, such as circular dichroism and optical rotatory dispersion, suffer from poor detection sensitivities and are limited by time-dependent backgrounds and/or by imperfect and slow subtraction procedures, and, as such, the need for a new technique is of great importance.
We are currently working on the construction of a novel polarimeter that will allows us to perform absolute chirality measurements with unprecedented sensitivity. This is possible by the use of an optical cavity that allows for amplification of the chiral signals, while introducing important signal reversals that enable the possibility for absolute measurements without the need for background removal. Using continuous-wave laser sources locked to stable high-finesse cavities and sensitive interferometric techniques, we aim towards chiral sensing capabilities several orders of magnitude more sensitive than traditional polarimetric techniques transforming thus the power of chirality detection in many fields.
This work is supported by the European Union’s Seventh Framework Programme for Research, Technological Development, and Demonstration, under the project ERA.Net RUS Plus, grant agreement no.189 (EPOCHSE), and by the European Union’s Horizon 2020 initiative FETOPEN-2014-2015-RIA, ULTRACHIRAL project (no. 737071).
 L. Bougas, D. Sofikitis, G. E. Katsoprinakis, A. K. Spiliotis, P. Tzallas, B. Loppinet, and T. P. Rakitzis, “Chiral Cavity Ring Down Polarimetry: Chirality and magnetometry measurements using signal reversals” J. Chem. Phys. 143, 104202 (2015).
 D. Sofikitis, L. Bougas, G. E. Katsoprinakis, A. K. Spiliotis, B. Loppinet, and T. P. Rakitzis, “Evanescent-wave and open-air chiral sensing via signal-reversing cavity-enhanced polarimetry”, Nature 514, 76 (2014).