Communications in Mathematical Sciences

Volume 19 (2021)

Number 4

Decoherence rhapsody in the photosynthesis process

Pages: 947 – 975



Claudia Negulescu (Université de Toulouse & Centre National de la Recherche Scientifique, Université Paul Sabatier, Institut de Mathématiques de Toulouse, France)


It is said that classical theories are sometimes inappropriate to describe very efficient biological processes in nature, which seem to be better understood via quantum mechanical models. We are however still very far from understanding how quantum features can survive in open quantum systems. In this paper the author shall present a simple mathematical model for the illustration of the excitation energy transfer in photosynthesis complexes, and shall study numerically the environment-induced decoherence effect and its influence on the emergence of classicality in nature. The model is based on the Schrödinger equation, describing the propagation of an absorbed excitation through a spin-chain towards a reaction center, and this in permanent interaction with a vibrational environment.


quantum mechanics, system-environment entanglement, decoherence, reduced density matrix, Schrödinger equation, numerical simulation, photosynthesis, spin-boson model, excitation energy transfer, spin-chain, harmonic-oscillator chain

2010 Mathematics Subject Classification

65Mxx, 65Zxx, 81P40, 81P45, 81Vxx

The author would like to acknowledge support from the CNRSIEA project No. 295470, “NASOQUAD” (Numerical and Analytical Study Of QUAntum Decoherence), 2020–2022.

Received 29 April 2020

Accepted 18 November 2020

Published 18 June 2021