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11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Heat exchange between two interacting nanoparticles beyond the fluctuation-dissipation regime.
Agustin Pérez-Madrid1, Luciano Calheiros Lapas, J Miguel Rubí
1Departament de Física Fonamental, Facultat de Física, Universitat de Barcelona, 08028 Barcelona, Spain. agustiperezmadrid@ub.edu
Physical Review Letters
|August 8, 2009
Summary
The nonmonotonic thermal conductance between nanoparticles arises from complex phase space dynamics. This dynamics, driven by thermally activated jumps over energy landscapes, explains heat transfer at contact.
Area of Science:
- Physics, Condensed Matter
- Nanotechnology
- Statistical Mechanics
Background:
- Thermal conductance measurements between nanoparticles reveal nonmonotonic behavior.
- Understanding heat transfer at the nanoscale, especially during contact, is crucial for device applications.
- The underlying dynamics of nanoparticle interactions during contact are not fully understood.
Purpose of the Study:
- To elucidate the origins of the nonmonotonic behavior in nanoparticle thermal conductance.
- To develop a theoretical framework for analyzing heat transfer dynamics just before and at the moment of nanoparticle contact.
- To investigate the role of phase space dynamics and energy landscape interactions.
Main Methods:
- Theoretical modeling of thermally activated jumping dynamics.
- Analysis of phase space dynamics in a rough energy landscape.
- Incorporation of a hierarchy of relaxation times to describe complex behavior.
- Examination of heat transfer mechanisms at the point of contact.
Main Results:
- The intricate phase space dynamics, driven by thermally activated jumps, directly causes the observed nonmonotonic thermal conductance.
- A hierarchy of relaxation times is identified as critical for describing the complex phase space behavior.
- The developed theory successfully analyzes heat transfer dynamics immediately preceding and during nanoparticle contact.
Conclusions:
- The nonmonotonic thermal conductance is a direct consequence of complex phase space dynamics.
- Thermally activated jumping through rough energy landscapes provides a robust explanation for nanoparticle thermal transport.
- The theoretical framework offers new insights into nanoscale heat transfer at the critical moment of contact.
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