https://doi.org/10.1140/epjb/e2012-30741-6
Regular Article
Effects of spatial dispersion on the Casimir force between graphene sheets
1 Department of Physics, University of
South Florida, 33620
Tampa, FL, USA
2 Department of Physics, North Carolina
Central University, 27707
Durham, NC, USA
3 Micro and Nanotechnology Centre,
Griffith University, Nathan, 4111
Queensland,
Australia
a e-mail: lmwoods@usf.edu
Received:
11
April
2012
Received in final form:
10
August
2012
Published online:
5
November
2012
The asymptotic dispersion force F between two graphene sheets at a separation d is unusual: at T = 0 K, F ~ Cd−p, where p = 4, unlike the 2D insulating (p = 5) or metallic (p = 7/2) cases. Here it is shown that these anomalous low-temperature properties of p are retained even when spatial dispersion (nonlocality) is included in the optical response properties of graphene. Furthermore, it is shown that the prefactor C is only weakly decreased (by <20%) upon spatial dispersion inclusion. For larger temperatures and nonzero chemical potential, such dispersion has even a lesser effect on the graphene/graphene force. The opening of a band gap in the graphene electronic structure, however, can cause larger sensitivity to spatial dispersion at elevated temperatures.
Key words: Mesoscopic and Nanoscale Systems
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag, 2012