TY - JOUR
T1 - Semimetallicity and electron-hole liquid in two-dimensional C and BN based compounds
AU - Lopez-Bezanilla, Alejandro
AU - Littlewood, Peter B.
N1 - Los Alamos National Laboratory is managed by Triad National Security, LLC, for the National Nuclear Security Administration of the U.S. Department of Energy under Contract No. 89233218CNA000001. We acknowledge the computing resources provided on Bebop, the high-performance computing cluster operated by the Laboratory Computing Resource Center at Argonne National Laboratory. Work at Argonne is supported by the Department of Energy, Office of Science, Basic Energy Sciences Division of Materials Science under Contract No. DE-AC02-06CH11357.
PY - 2021/1/29
Y1 - 2021/1/29
N2 - An insulating-metallic transition mediated by substitutional atoms is predicted in a series of two-dimensional carbon-based structures. Introducing Si atoms in selected sites of tetrahexcarbon [B. Ram and H. Mizuseki, Carbon 137, 266 (2018)CRBNAH0008-622310.1016/j.carbon.2018.05.034] according to rational chemical rules, metallicity by trivial band inversion without a band gap opening is induced. Additional substitution of the remaining C atoms by BN dimers introduces no changes in the metallic properties. A series of isomorphous two-dimensional materials with isoelectronic structures derived by exchanging group IV elements exhibiting various band gaps is obtained. Dynamical stability is verified with a phonon analysis and beyond the harmonic approximation with molecular dynamics up to room temperature. The semimetallic compounds have well-nested pockets of carriers and are good candidates for the formation of an excitonic insulator.
AB - An insulating-metallic transition mediated by substitutional atoms is predicted in a series of two-dimensional carbon-based structures. Introducing Si atoms in selected sites of tetrahexcarbon [B. Ram and H. Mizuseki, Carbon 137, 266 (2018)CRBNAH0008-622310.1016/j.carbon.2018.05.034] according to rational chemical rules, metallicity by trivial band inversion without a band gap opening is induced. Additional substitution of the remaining C atoms by BN dimers introduces no changes in the metallic properties. A series of isomorphous two-dimensional materials with isoelectronic structures derived by exchanging group IV elements exhibiting various band gaps is obtained. Dynamical stability is verified with a phonon analysis and beyond the harmonic approximation with molecular dynamics up to room temperature. The semimetallic compounds have well-nested pockets of carriers and are good candidates for the formation of an excitonic insulator.
KW - Excitons
KW - Two-dimensional electron systems
KW - Density functional calculations
U2 - 10.1103/PhysRevMaterials.5.014006
DO - 10.1103/PhysRevMaterials.5.014006
M3 - Article
AN - SCOPUS:85100428159
SN - 2475-9953
VL - 5
JO - Physical Review Materials
JF - Physical Review Materials
IS - 1
M1 - 014006
ER -