Understanding cohesive forces in Nanosystems

International Collaboration

Status: finished project
Contract Number:
DP1096240
Starting date 
1 January 2010
Ending date 
31 December 2012

ARC (Australian Research Council) Discovery Project

Nanostructures such as carbon nanotubes, graphene sheets, bucky balls, functional monolayers, bio-nanostructures and nano-sized magnetic particles are central to new generations of technology. Applications include nano-electro-mechanical devices, advanced materials and textiles, ultra-small electronic circuit elements for high-density information storage and processing, and magnetic nano-particles for medical diagnostics and drug delivery, as well as in ferrofluids. Cohesion of these systems is typically via “residual” forces such as the dispersion (van der Waals, vdW, Casimir) attraction that bind the nano-sized components into useful structures, and that arise from intrinsic quantal or thermal fluctuations. These forces were generally considered to be quite well understood, but some surprising behaviour has recently been uncovered.

This necessitates a fresh look at the theory, as proposed in the present Project, in order to provide sufficiently accurate predictive and modelling power. Several related sub-projects will be tackled, with a common thread of treating the correlations and fluctuations in a microscopic quantum theory approach, in order to obtain the residual forces. The general aims are

  • To remedy some deficiencies in the current theory of dispersion forces, thereby allowing realistic modelling of nanostructure cohesion, especially in graphene-based systems.
  • To make this extended physics available without massive computational effort, by using new insights to extend the well-known Lifshitz and Local Density approximations
  • To use related theory to investigate magnetic analogues of the van der Waals force in superparamagnetic nanoparticles, relevant to medical therapies, data storage and ferrofluids.

Personal

  • JF Dobson (Griffith University, Australia)
  • A Rubio (UPV/EHU, Spain)
  • A Savin (Université de Paris 6, France)
  • G Vignale (University of Missouri, Columbia, USA)