Electronic structures of hexagonal boron-nitride monolayer: Strain-induced effects

First-principles electronic-structure calculations have been performed to examine electronic properties of hexagonal boron nitride (h-BN) monolayers. The dispersion of the energy bands and the width of the band gaps are calculated under biaxial strains. It is found that the band gap decreases as the tensile strain increases, whereas the band gap increases and then it decreases as the compressive strain increases. The relationship between the energy-band structures and the applied strains is reported to clarify the unique behaviors of the band gaps induced by biaxial strains.