Tunable interfacial thermal conductance in graphene/germanene van der Waals heterostructure using an optimized...

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Modeling interfacial thermal transport in van der Waals heterostructures is crucial but limited by the lack of accurate interlayer potentials.
• Graphene and germanene van der Waals heterostructures are promising for advanced electronic and thermal applications.

Purpose of the Study:

• To develop a novel pairwise interlayer potential for graphene/germanene heterostructures.
• To investigate the interfacial thermal conductivity and its tunability using the developed potential.
• To understand the influence of external strain, temperature, and interaction strength on thermal transport.

Main Methods:

• Ab initio density functional theory (DFT) calculations to obtain binding energy.
• Development of a pairwise interlayer potential based on DFT results.
• Calculation of interfacial thermal conductivity using the developed potential.
• Phonon density of states analysis to understand strain effects.

Main Results:

• The developed interlayer potential accurately models graphene/germanene heterostructures.
• Interfacial thermal conductivity is highly tunable with external strain.
• Compressive strain along the heat flow direction increases interfacial thermal conductance (ITC) to ~136% of the unstrained value.
• Tensile strain reduces ITC to ~70% of the unstrained value.
• Both temperature and interlayer interaction strength positively correlate with ITC.

Conclusions:

• The developed interlayer potential provides a reliable method for studying thermal transport in graphene/germanene heterostructures.
• External strain offers an effective route to control interfacial thermal conductivity in these materials.
• Understanding these thermal transport mechanisms is vital for designing next-generation thermal management devices.