Defect Behavior in Hexagonal Boron Nitride (h-BN) under Strain

Hexagonal boron nitride (h-BN) is a layered van der Waals material characterized by a large electronic band gap, which supports its widespread application in two-dimensional electronic devices as an insulating layer and as a host for stable, bright single-photon emitters (SPEs). h-BN emits photons across a broad spectral range from ultraviolet to near-infrared, facilitating compatibility with diverse technological platforms. Atomic-scale photon emitters are critical for quantum information processing, secure quantum communication, and high-precision quantum sensing. The performance of these applications depends on the presence and control of specific atomic defects within the h-BN crystal lattice, making precise defect manipulation a central research focus. Strain engineering provides a versatile method for tuning the optical and electronic properties of h-BN, including defect behavior in h-BN. This research uses hybrid density functional theory (DFT) calculations to investigate the electronic structure, stability, and optical properties of boron vacancy defects in bulk h-BN under uniaxial and biaxial strain. The correlation between mechanical deformation and changes in defect formation energies, electronic band structure, charge state transition levels, and optical characteristics is systematically investigated. The findings offer theoretical insights into defect behavior in h-BN and inform targeted material design.