A simple model of the charge transfer in DNA-like substances

TL;DR

This paper introduces a simplified nonlinear Schrödinger equation model to study charge transfer in DNA-like molecules, highlighting how electronic coupling influences localization and soliton behavior.

Contribution

It proposes a new minimal model using a discrete nonlinear Schrödinger equation to analyze charge transport in DNA-like structures, emphasizing the role of the coupling parameter J.

Findings

Lower J values lead to localized charge states.

Higher J values produce spread-out soliton fields.

Charge transport behavior depends on the coupling parameter J.

Abstract

We present a very simple model for the study of charge transport in a molecule patterned on B-DNA. In this model we use a discrete non-linear Schr\"{o}dinger equation to describe electrons propagating along the sugar-phosphate backbone of the DNA molecule. We find that in this model, for a given nonlinearity, the transport is controlled by $J$, a parameter which relates to the electronic coupling between different molecules on the backbone. For smaller values of $J$ we have localised states while at higher values of $J$ the soliton field is spread out and through its interaction with the lattice it has stronger effects on the distortion of the lattice.