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Title: Flexoelectricity in atomic monolayers from first principles
We study the flexoelectric effect in fifty-four select atomic monolayers using ab initio Density Functional Theory (DFT). Specifically, considering representative materials from each of the Group III monochalcogenides, transition metal dichalcogenides (TMDs), Groups IV, III–V, and V monolayers, Group IV dichalcogenides, Group IV monochalcogenides, transition metal trichalcogenides (TMTs), and Group V chalcogenides, we perform symmetry-adapted DFT simulations to calculate transversal flexoelectric coefficients along the principal directions at practically relevant bending curvatures. We find that the materials demonstrate linear behavior and have similar coefficients along both principal directions, with values for TMTs being up to a factor of five larger than those of graphene. In addition, we find electronic origins for the flexoelectric effect, which increases with monolayer thickness, elastic modulus along the bending direction, and sum of polarizability of constituent atoms.  more » « less
Award ID(s):
1828187
PAR ID:
10318229
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Nanoscale
Volume:
13
Issue:
3
ISSN:
2040-3364
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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