Robust Multicolor Single Photon Emission from Point Defects in Hexagonal Boron Nitride

TLDR

Hexagonal boron nitride (hBN) is an emerging two‑dimensional material for quantum photonics owing to its large bandgap and hyperbolic properties. The study reports two methods—electron beam irradiation and annealing—to engineer quantum emitters in hBN multilayers and characterizes their photophysical properties. The authors created point defects by electron beam irradiation or thermal annealing in hBN multilayers and then characterized the resulting emitters. The engineered emitters display robust, room‑temperature, multicolor single‑photon emission with sub‑10 nm linewidths, short lifetimes, and high brightness, remain stable under harsh annealing, and suggest deterministic control of 2D quantum emitters for quantum information and nanophotonics.

Abstract

Hexagonal boron nitride (hBN) is an emerging two-dimensional material for quantum photonics owing to its large bandgap and hyperbolic properties. Here we report two approaches for engineering quantum emitters in hBN multilayers using either electron beam irradiation or annealing and characterize their photophysical properties. The defects exhibit a broad range of multicolor room-temperature single photon emissions across the visible and the near-infrared spectral ranges, narrow line widths of sub-10 nm at room temperature, and a short excited-state lifetime, and high brightness. We show that the emitters can be categorized into two general groups, but most likely possess similar crystallographic structure. Remarkably, the emitters are extremely robust and withstand aggressive annealing treatments in oxidizing and reducing environments. Our results constitute a step toward deterministic engineering of single emitters in 2D materials and hold great promise for the use of defects in boron nitride as sources for quantum information processing and nanophotonics.