Complementary local-global approach for phonon mode connectivities

Abstract

Sorting and assigning phonon branches (e.g., longitudinal acoustic) of phonon modes is important for characterizing the phonon bands of a crystal and the determination of phonon properties such as the Grüneisan parameter and group velocity. To do this, the phonon band indices (including the longitudinal and transverse acoustic) have to be assigned correctly to all phonon modes across a path or paths in the Brillouin zone. As our solution to this challenging problem, we propose a computationally efficient and robust two-stage hybrid method that combines two approaches with their own merits. The first is the perturbative approach in which we connect the modes using degenerate perturbation theory. In the second approach, we use numerical fitting based on least-squares fits to circumvent local connectivity errors at or near exact degenerate modes. The method can be easily generalized to other condensed matter problems involving Hermitian matrix operators such as electronic bands in tight-binding Hamiltonians or in a standard density-functional calculation, and photonic bands in photonic crystals.

arXiv comment6 figures, 7 pages

References in corpus (13)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Phonons and related properties of extended systems from density-functional perturbation theory
• Berry Phase Effects on Electronic Properties
• Optimized Tersoff and Brenner empirical potential parameters for lattice dynamics and phonon thermal transport in carbon nanotubes and graphene
• High-accuracy first-principles determination of the structural, vibrational and thermodynamical properties of diamond, graphite, and derivatives
• The Effect of Lattice Vibrations on Substitutional Alloy Thermodynamics
• First-principles study of the lattice dynamics of Sb2S3
• Anharmonic interatomic force constants and thermal conductivity from Grüneisen parameters: an application to graphene
• Large anharmonic effect and thermal expansion anisotropy of metal chalcogenides: The case of antimony sulfide
• Characterization of Zero-point Vibration in One-Component Crystals
• Anharmonic phonon effects on linear thermal expansion of trigonal bismuth selenide and antimony telluride crystals
• Efficacious symmetry-adapted atomic displacement method for lattice dynamical studies
• Large thermal anisotropy in monoclinic niobium trisulfide: A thermal expansion tensor study

Cited by in corpus (4)

• cij: A Python code for quasiharmonic thermoelasticity
• Specular transmission and diffuse reflection in phonon scattering at grain boundary
• Effect of boundary roughness on the attenuation of specular phonon reflection in graphene
• A size-consistent Grüneisen-quasiharmonic approach for lattice thermal conductivity