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arXiv · 1708.00384

Comment on "Piezoelectricity in planar boron nitride via a geometric phase"

Jie Li·Yunhua Wang·Zongtan Wang·Jie Tan·Biao Wang·Yulan Liu
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Abstract

Using the strain-dependent effective Hamiltonian and the geometric phase, Droth et al. [Phys. Rev. B 94, 075404 (2016)] obtain an analytical expression for the electronic contribution to the piezoelectricity of planar hexagonal boron nitride (h -BN). Their analytical results of piezoelectric constants for h -BN are invalid because of the mistakes in constructing the adiabatic process of the piezoelectricity. In this comment, we reconstruct a proper adiabatic process for piezoelectricity and formulate a general Berry phase expression for the piezoelectric coefficients of two-dimensional piezoelectric crystals by means of the modern theory of polarization. The corrected analytical results of the piezoelectric constants are in complete consistency with the first-principles calculations and hence manifest the validity and generality of the Berry phase expression of piezoelectric coefficients.

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Jie Li, Yunhua Wang, Zongtan Wang, Jie Tan, Biao Wang, Yulan Liu. 2017-08-01. Comment on "Piezoelectricity in planar boron nitride via a geometric phase". https://doi.org/10.1103/physrevb.98.167403

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