Stability and electronic properties of atomic layers of GaN are investigated in the framework of the van der Waals-density functional theory. We find that the ground state of the layered GaN is a planar graphene-like configuration rather than a buckled bulk-like configuration. Application of an external perpendicular electric field to the layered GaN induces distinct stacking-dependent features of the tunability of the band gap; the band gap of the monolayer does not change whereas that of the trilayer GaN is significantly reduced for the applied field of 0.4 V/ {\AA}. It is suggested that such a stacking-dependent tunability of the band gap in the presence of an applied field may lead to novel applications of the devices based on the layered GaN.
@article{arxiv.1302.5157,
title = {Stacking and electric field effects on the electronic properties of the layered GaN},
author = {Dongwei Xu and Haiying He and Ravindra Pandey and Shashi P. Karna},
journal= {arXiv preprint arXiv:1302.5157},
year = {2013}
}