Modeling Interlayer Interactions and Phonon Thermal Transport in Silicene Bilayer

Abstract

We develop an accurate interlayer pairwise potential derived from the \textit{ab-initio} calculations and investigate the thermal transport of silicene bilayers within the framework of equilibrium molecular dynamics simulations. The electronic properties are found to be sensitive to the temperature with the opening of the band gap in the $\Gamma$$\to$M direction. The calculated phonon thermal conductivity of bilayer silicene is surprisingly higher than that of monolayer silicene, contrary to the trends reported for other classes of 2D materials like graphene and hBN bilayers. This counterintuitive behavior of the bilayer silicene is attributed to the interlayer interaction effects and inherent buckling, which lead to a higher group velocity in the LA${}_1$/LA${}_2$ phonon modes. The thermal conductivity of both the mono- and bilayer silicene decreases with temperature as $\kappa \sim T^{-0.9}$ because of the strong correlations between the characteristic timescales of heat current autocorrelation function and temperature ($\tau \sim T^{-0.75}$). The mechanisms underlying phonon thermal transport in silicene bilayers are further established by analyzing the temperature induced changes in acoustic group velocity.

arXiv commentTo appear in Phys. Rev. B

References in corpus (23)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Advanced capabilities for materials modelling with Quantum ESPRESSO
• Quantum Spin Hall Effect in Silicene
• Optimized Tersoff and Brenner empirical potential parameters for lattice dynamics and phonon thermal transport in carbon nanotubes and graphene
• Electrically Tunable Band Gap in Silicene
• Phononic thermal properties of two-dimensional materials
• Prediction of Near-Room-Temperature Quantum Anomalous Hall Effect on Honeycomb Materials
• Effect of substrate modes on thermal transport in supported graphene
• Unexpectedly Large Tunability of Lattice Thermal Conductivity of Monolayer Silicene via Mechanical Strain
• d+id' Chiral Superconductivity in Bilayer Silicene
• Thermal conductivity decomposition in two-dimensional materials: Application to graphene
• Tensile Strains Give Rise to Strong Size Effects for Thermal Conductivities of Silicene, Germanene and Stanene
• Controllable Thermal Conductivity in Twisted Homogeneous Interfaces of Graphene and Hexagonal Boron Nitride
• Dihedral-angle-corrected registry-dependent interlayer potential for multilayer graphene structures
• Stabilized silicene within bilayer graphene: A proposal based on molecular dynamics and density-functional tight-binding calculations
• Manipulating thermal conductivity through substrate coupling
• Structural stability and energy-gap modulation through atomic protrusion in freestanding bilayer silicene
• Phonons and Thermal Conducting Properties of Borocarbonitride (BCN) Nanosheets
• Diverse Magnetic Quantization in Bilayer Silicene
• Fully Spin-Polarized Current in Gated Bilayer Silicene
• Exploring the stability of twisted van der Waals heterostructures
• Thermodynamic properties of graphene bilayers
• Valley- and spin-dependent quantum Hall states in bilayer silicene

Cited by in corpus (3)

• Nontrivial impact of interlayer coupling on thermal conductivity: opposing trends in in-plane and out-of-plane phonons
• Anomalous Temperature Induced Transition and Convergence of Thermal Conductivity in Germanene Monolayer
• Tunable Interfacial Thermal Conductance in Graphene/Germanene van der Waals Heterostructure using an Optimized Interlayer Potential