Single-photon emission from two-dimensional hexagonal boron nitride annealed in a carbon-rich environment

Abstract

For quantum photonic applications, such as quantum communication, optical quantum information processing, and metrology, solid-state sources of single-photon emitters are highly needed. Recently, single-photon emitters in two-dimensional (2D) van der Waals materials have attracted tremendous attention because of their atomic thickness, allowing for high photon extraction efficiency and easy integration into photonic circuits. In particular, a defect hosted by 2D hexagonal boron nitride (hBN) is expected to be a promising candidate for next-generation single-photon sources due to its chemical and thermal stability and high brightness at room temperature. Here, we report an effective method for generating single-photon emission in mechanically exfoliated hBN flakes by annealing in a carbon-rich environment. The one-step annealing in a mixed atmosphere (Ar:CH4:H2 = 15:5:1) greatly increases the single-photon emitter density in hBN. The resulting single-photon emission shows high stability and brightness. Our results provide an effective method for generating room-temperature single-photon emitters in 2D hBN.