Thermopower of Graphene Nanoribbons in the Pseudodiffusive Regime

TL;DR

This paper investigates the thermopower of graphene nanoribbons in the pseudodiffusive regime, analyzing how aspect ratio, chemical potential, and temperature influence thermoelectric properties, with results aligning well with experimental data.

Contribution

It provides a theoretical analysis of thermopower in graphene ribbons considering the pseudodiffusive regime, incorporating key parameters like aspect ratio, chemical potential, and temperature.

Findings

Thermopower depends on aspect ratio, chemical potential, and temperature.

Numerical results agree with experimental measurements on disordered graphene ribbons.

The study advances understanding of thermoelectric behavior in graphene nanostructures.

Abstract

Thermoelectric measurements for graphene ribbons are currently performed on samples that include atomic disorder via defects and irregular edges. In this work, we investigate the thermopower or Seebeck coefficient of graphene ribbons within the linear response theory and the Landauer formalism, and we consider the diffusive regime taken as a limit of the ribbon aspect ratio. We find that the thermopower and the electronic conductivity depend not only on the aspect ratio, but also on chemical potential and temperature, which are set here as key parameters. The obtained numerical results with temperature and doping are brought into contact with the thermoelectric measurements on disordered graphene ribbons with good agreement.