Two-dimensional materials offer novel quantum electro-optical and magneto-optical properties. Defects play a crucial role in quantum photonics with hBN: on one hand, atomic defects in hBN behave as bright single-photon emitters operating at room temperature. On the other hand, defects also reduce phonon lifetimes which can be detrimental to infrared nanophotonic. Moreover, defect engineering is now becoming a common approach to localize charge and manipulate the optical excitations, determining their lifetimes, associated to the underlying spin and valley selectivity. Understanding the crystallographic structure, the effect of defect concentration, and their role in emission is thus critical for the design of 2D single-photon emitters based on defect engineering.

Defects are a complex problem because it requires exploring a large configurational space with sampling methods and characterizing the influence of defects on electro- and magneto-optical properties using first principles methods. Moreover, at finite temperatures, thermal effects, including lattice expansion, ripples, and entropic contributions, all influence the structures and stabilities of the defects. TIMES network combine expertise on first principles methods with molecular dynamics simulations to tackle this challenge.