Optical Activity and Circular Dichroism of Perovskite Quantum-Dot Molecules

Abstract

Great prospects of using chiral molecules made of semiconductor quantum dots (QDs) as readjustable elements of optically active materials and devices offer them as a potential material base for chiral nanophotonics. This article presents a rigorous theoretical framework for the analysis of optical activity of chiral QD molecules composed of an arbitrary number of achiral QDs. We show the power of the proposed framework by analytically calculating the rotatory strengths and dissymmetry factors of quantum transitions to the excited molecular states of a QD molecule made of two perovskite QDs. The analysis of the obtained characteristics leads us to the optimal mutual orientations of the QDs, which correspond to the maximal rotatory strengths and the ultimate values of the dissymmetry factors. The peak rotatory strengths are shown to reach 10–35 erg × cm3, exceeding the typical rotatory strengths of chiral molecules by 4 orders of magnitude. The developed theoretical framework equips physicists and engineers with a powerful tool for the modeling and engineering of optically active QD molecules for nanophotonics applications.