Paving the Way Towards a Compact Complete Chiroptical Toolbox

Circularly polarised luminescence (CPL) spectroscopy is a technique with applications in materials chemistry, bioimaging, probing fundamental chirality, but conventional photo-elastic modulator CPL instruments remain bulky, expensive and slow. We report a compact single-channel CPL (SC-CPL) spectrometer that alternates left-and righthanded emission through a piezo-actuated pair of orthogonally aligned achromatic quarter-wave plates using a rapid CCD detector. This design minimises moving optics and eliminates the need for detector matching and pre-calibration. It can operate in various acquisition modes such as time gated acquisition mode for long-lived CPL emission and a quasi-continuous mode for short-lived CPL emission. Validation against a benchmark PEM-CPL system using a range of CPL emitters reproduced fine CPL resolution with high sensitivity, orders of magnitude faster. This blueprint SC-CPL reported herein paves the way towards the world's first complete compact chiroptical toolbox. This could lead to significant advancements with pivotal scientific and societal impact.