Edge reconstruction in armchair phosphorene nanoribbons revealed by discontinuous Galerkin density functional theory

Abstract

With the help of our recently developed massively parallel DGDFT (Discontinuous Galerkin Density Functional Theory) methodology, we perform large-scale Kohn-Sham density functional theory calculations on phosphorene nanoribbons with armchair edges (ACPNRs) containing a few thousands to ten thousand atoms. The use of DGDFT allows us to systematically achieve conventional plane wave basis set type of accuracy, but with a much smaller number (about 15) of adaptive local basis (ALB) functions per atom for this system. The relatively small number degrees of freedom required to represent the Kohn-Sham Hamiltonian, together with the use of the pole expansion the selected inversion (PEXSI) technique that circumvents the need to diagonalize the Hamiltonian, result in a highly efficient and scalable computational scheme for analyzing the electronic structures of ACPNRs as well as its dynamics. The total wall clock time for calculating the electronic structures of large-scale ACPNRs containing 1080-10800 atoms is only 10-25 s per self-consistent field (SCF) iteration, with accuracy fully comparable to that obtained from conventional planewave DFT calculations. For the ACPNR system, we observe that the DGDFT methodology can scale to 5,000-50,000 processors. We use DGDFT based ab-initio molecular dynamics (AIMD) calculations to study the thermodynamic stability of ACPNRs. Our calculations reveal that a 2 * 1 edge reconstruction appears in ACPNRs at room temperature.

9 pages, 5 figures

References in corpus (8)

• Electric Field Effect in Atomically Thin Carbon Films
• The electronic properties of graphene
• Detection of Individual Gas Molecules Absorbed on Graphene
• Energy Gaps in Graphene Nanoribbons
• Substrate-induced band gap opening in epitaxial graphene
• Biased bilayer graphene: semiconductor with a gap tunable by electric field effect
• Phosphorene nanoribbons, nanotubes and van der Waals multilayers
• Electronic Structure of Large-Scale Graphene Nanoflakes

Cited by in corpus (8)

• Defect in Phosphorene
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• Chebyshev polynomial filtered subspace iteration in the Discontinuous Galerkin method for large-scale electronic structure calculations
• Influence of Edge Functionalization on Electronic and Optical Properties of Armchair Phosphorene Nanoribbons: a First-Principles Study
• Adaptive local basis set for Kohn-Sham density functional theory in a discontinuous Galerkin framework II: Force, vibration, and molecular dynamics calculations
• Discontinuous Galerkin discretization for quantum simulation of chemistry
• Interpolative Separable Density Fitting through Centroidal Voronoi Tessellation With Applications to Hybrid Functional Electronic Structure Calculations
• Two-level Chebyshev filter based complementary subspace method: pushing the envelope of large-scale electronic structure calculations