Förster Coupling in Nanoparticle Excitonic Circuits

Abstract

Exciton transport in semiconductor nanoparticles underlies recent experiments on electrically controlled excitonic circuits and proposals for new artificial light-harvesting systems. In this work, we develop a new method for the numerical evaluation of the Förster matrix element, based on a three-dimensional real space grid and the self-consistent solution of the mesoscopic exciton in a macroscopic dielectric environment. This method enables the study of the role of the nanoparticle shape, spatially varying dielectric environment, and externally applied electric fields. Depending on the orientation of the transition dipole, the Förster coupling is shown to be either increased or decreased as a function of the nanoparticle shape and of the properties of the dielectric environment. In the presence of an electric field, we investigate the relation between excitonic binding and confinement effects. We also study a type II core-shell quantum dot where electron and hole are spatially separated due to a particular configuration of the bandstructure.

Quantum Chemical Studies of Light Harvesting

“…Still following a Coulomb scheme, the role of a complex dielectric environment (and external electric fields) in the coupling of QD has been also investigated. 316 A self-consistent solution of the Schrodinger and Poisson equations was introduced to calculate the Forster coupling between nanoparticles of arbitrary size, shape, and orientation, embedded in an arbitrarily complex electrostatic environment of positiondependent dielectric constant ε(r). The Forster coupling was shown to be either increased or decreased as a function of the nanoparticle shape and of the properties of the dielectric environment.…”

Anion Stabilization in Electrostatic Environments

“…This treatment of gated systems has enabled the study of properties such as Coulomb blockade energetics, 25 quantum-dots selfconsistent structures 26 and more recently, Förster coupling in nanoparticle excitonic circuits. 27 In this work we focus on molecular systems interacting with a nanoscale environment. As a representative example, we study the benzene anion.…”

The role of interparticle interaction and environmental coupling in a two-particle open quantum system

“…Interest in OQS goes from studies of the influence of the environment on quantum properties in the quantum-classical transition [6,7,8,9,10,11], to the study of the influence of the bath in uncertainty relations and the separation between quantum and thermal fluctuations [12,13,14,15,16,17]. Other important examples of OQS are photo-absorption of chromophores in a protein bath [18,19,20,21], electron-phonon coupling in single-molecule transport [22,23,24,25,26,27] and exciton and energy transfer [28,29,30,31]. Some of these studies have used the Shannon entropy from information theory as a tool to analyze the localization properties of the underlying distributions.…”