Abstract

We develop a low-energy continuum model for phonons in twisted moiré bilayers, based on a configuration-space approach. Interatomic force constants are obtained from density functional theory calculations of untwisted bilayers with various in-plane shifts, enabling efficient computation of phonon properties for any small twist angle while maintaining DFT-level accuracy. The model is applied to bilayer graphene, bilayer MoS2, and MoSe₂-WSe₂ heterostructures to analyze low-energy phonon modes, including interlayer shearing and layer-breathing modes, as a function of twist angle.

Abstract

We develop a low-energy continuum model for phonons in twisted moiré bilayers, based on a configuration-space approach. Interatomic force constants are obtained from density functional theory calculations of untwisted bilayers with various in-plane shifts, enabling efficient computation of phonon properties for any small twist angle while maintaining DFT-level accuracy. The model is applied to bilayer graphene, bilayer MoS2, and MoSe₂-WSe₂ heterostructures to analyze low-energy phonon modes, including interlayer shearing and layer-breathing modes, as a function of twist angle.

Abstract

We develop a low-energy continuum model for phonons in twisted moiré bilayers, based on a configuration-space approach. Interatomic force constants are obtained from density functional theory calculations of untwisted bilayers with various in-plane shifts, enabling efficient computation of phonon properties for any small twist angle while maintaining DFT-level accuracy. The model is applied to bilayer graphene, bilayer MoS2, and MoSe₂-WSe₂ heterostructures to analyze low-energy phonon modes, including interlayer shearing and layer-breathing modes, as a function of twist angle.

Abstract

We develop a low-energy continuum model for phonons in twisted moiré bilayers, based on a configuration-space approach. Interatomic force constants are obtained from density functional theory calculations of untwisted bilayers with various in-plane shifts, enabling efficient computation of phonon properties for any small twist angle while maintaining DFT-level accuracy. The model is applied to bilayer graphene, bilayer MoS2, and MoSe₂-WSe₂ heterostructures to analyze low-energy phonon modes, including interlayer shearing and layer-breathing modes, as a function of twist angle.