High current density electron wind forces in metallic graphene nanoribbons.

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Graphene nanoribbons (GNRs) exhibit unique electronic properties.
• Understanding electron-phonon interactions is crucial for GNR applications.
• Electric current can induce mechanical stress in nanostructures.

Purpose of the Study:

• To calculate electric current-induced wind forces on zigzag graphene nanoribbons (ZGNRs).
• To compare wind forces and Joule heating in ZGNRs with carbon nanotubes.
• To investigate the primary failure mechanism of GNRs under electric current.

Main Methods:

• Semi-classical method integrating quantum mechanics into ensemble Monte Carlo simulations.
• Consideration of energy and momentum conservation during electron-phonon scattering.
• First-order perturbation theory with deformation potential approximation for scattering rates.

Main Results:

• Joule heating power in a 10-dimer ZGNR is ~3 orders of magnitude higher than in metallic single-walled carbon nanotubes.
• Wind forces in ZGNRs are ~1 order of magnitude higher than in carbon nanotubes.
• Calculated wind force (0.0073 eV Å⁻¹ at 20 kV, 300 K) is significantly lower than ZGNR fracture strength.

Conclusions:

• The failure of GNRs under electric current is primarily attributed to Joule heating, not wind forces.
• ZGNRs experience substantial wind forces and Joule heating when subjected to electric fields.
• The findings provide insights into the mechanical stability of GNRs under electrical load.