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Nonequilibrium heat flows through a nanorod sliding across a surface
Alexander V Popov1, Douglas C Viehman, Rigoberto Hernandez
1Center for Computational and Molecular Science and Technology, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia, USA.
The Journal of Chemical Physics
|March 17, 2011
Summary
This study models nanorod-surface friction using a Langevin equation, separating the environment into equilibrium and nonequilibrium baths. Results align with molecular dynamics simulations for atomic oscillations and temperature effects.
Area of Science:
- Materials Science
- Surface Physics
- Computational Chemistry
Background:
- Previous studies modeled nanorod-surface interactions using hydroxylated α-Al(2)O(3) layers.
- Molecular dynamics (MD) simulations by Hase and co-workers provided insights into these interactions.
Purpose of the Study:
- To describe nonequilibrium atomic oscillations of a nanorod dragged across a surface.
- To apply a reduced Frenkel-Kontorova-Tomlinson model to nanorod-surface dynamics.
- To introduce a novel approach separating the environment into two effective baths.
Main Methods:
- Utilized the temperature-ramped irreversible Langevin equation.
- Modeled the system as a reduced Frenkel-Kontorova-Tomlinson model.
- Separated the environment into an equilibrium bath (crystal lattice vibrations) and a nonequilibrium bath (nanorod-surface contact oscillations).
Main Results:
- The model successfully describes nonequilibrium atomic oscillations of the nanorod.
- The temperature of the nonequilibrium bath is defined by the mean energy of a representative atomic oscillator.
- Temporal temperature fluctuations and static temperature dependence on sliding velocity match MD simulation results.
Conclusions:
- The proposed model provides a framework for understanding friction at the nanoscale.
- The separation into two baths offers a new perspective on environmental effects in driven systems.
- The findings are consistent with established simulation data, validating the approach.
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