Thickness- and temperature-dependent Grüneisen parameter in thin films

Area of Science:

• Materials Science
• Condensed Matter Physics
• Thermodynamics

Background:

• The Grüneisen parameter is vital for linking mechanical and thermal properties of materials.
• Understanding its behavior in thin films is essential for advanced material applications.

Purpose of the Study:

• To investigate the Grüneisen parameter's dependence on film thickness and temperature.
• To develop theoretical models and validate them with molecular dynamics simulations.

Main Methods:

• Theoretical modeling yielding two analytic expressions for the Grüneisen parameter.
• Molecular dynamics (MD) simulations on FCC Ni, Cu, and Au (001) thin films and bulk materials.

Main Results:

• Theoretical predictions for the thickness- and temperature-dependent Grüneisen parameter were confirmed by MD simulations.
• Parameters within the theoretical model were determined.
• Film heat capacity density was also analyzed in relation to the Grüneisen parameter.

Conclusions:

• The study successfully models the Grüneisen parameter's dependency on film thickness and temperature.
• MD simulations provide robust validation for the theoretical framework.
• This work enhances the understanding of thermal and mechanical properties in nanomaterials.