Influence of Complex Exciton-Phonon Coupling on Optical Absorption and Energy Transfer of Quantum Aggregates

TL;DR

This paper introduces a stochastic theoretical framework to accurately model the quantum dynamics of electronic excitations coupled to complex phonon environments, enabling better understanding of optical and energy transfer properties in quantum aggregates.

Contribution

It develops a novel stochastic approach for non-Markovian open quantum systems that handles realistic, structured phonon environments where traditional methods fail.

Findings

Successfully calculates spectra and energy transfer dynamics of molecular aggregates.

Elucidates the transition from coherent to incoherent energy transfer.

Demonstrates the method's efficiency and applicability to complex systems.

Abstract

We present a theory that efficiently describes the quantum dynamics of an electronic excitation that is coupled to a continuous, highly structured phonon environment. Based on a stochastic approach to non-Markovian open quantum systems, we develop a dynamical framework that allows us to handle realistic systems where a fully quantum treatment is desired yet the usual approximation schemes fail. The capability of the method is demonstrated by calculating spectra and energy transfer dynamics of mesoscopic molecular aggregates, elucidating the transition from fully coherent to incoherent transfer.