Quantum emitters in bilayer hexagonal boron nitride

TL;DR

This study investigates how defect interactions in bilayer hexagonal boron nitride can enhance and tune single-photon emission properties, providing insights for quantum photonics applications.

Contribution

It demonstrates that atomic defect interactions in bilayer hBN introduce new spectral features, enabling engineered single-photon emission through defect placement and orientation.

Findings

Defect interactions in bilayer hBN create new polarization-dependent spectral features.

The spectral features depend strongly on defect distance and orientation.

Results suggest pathways for engineering quantum emitters in hBN.

Abstract

Hexagonal boron nitride (hBN) has been experimentally shown to exhibit room-temperature single-photon emission. This emission is attributed to defect states in the wide band-gap of hBN, which allow new optical transitions between these dispersion-less defect levels. In this work, we study the new spectral features introduced by interacting atomic defects in consecutive layers of bilayer hBN. Density Functional theory simulations have been carried out to calculate the energy band structure, frequency-dependent complex dielectric functions, and Kohn-Sham states to demonstrate and understand the cause of the emission enhancements. We found that placing colour centres in the vicinity of each other in bilayer hBN introduces new polarization dependent spectral features, with strong dependence on the distance and relative orientation between atomic defects. Our results provide a pathway to engineering single photon emission in hBN via inter-defect interaction.