Vibrational signatures for the identification of single-photon emitters in hexagonal boron nitride

TL;DR

This study uses first-principles calculations to analyze vibrational signatures of defects in hexagonal boron nitride, aiding the identification of single-photon emitters for quantum technologies.

Contribution

It systematically elucidates defect-vibrational coupling in h-BN, linking specific defects to experimental emission lineshapes for the first time.

Findings

Strong coupling of defects to high-frequency phonons.

Identification of specific defects matching experimental lineshapes.

Guidance for selecting optically active defects in quantum applications.

Abstract

Color centers in h-BN are among the brightest emission centers known yet the origins of these emission centers are not well understood. Here, using first-principles calculations in combination with the generating function method, we systematically elucidate the coupling of specific defects to the vibrational degrees of freedom. We show that the lineshape of many defects exhibits strong coupling to high frequency phonon modes and that C$_{\text{N}}$, C$_{\text{B}}$, C$_{\text{B}}$-C$_{\text{N}}$ dimer and V$_{\text{B}}$ can be associated with experimental lineshapes. Our detailed theoretical study serves as a guide to identify optically active defects in h-BN that can suit specific applications in photonic-based quantum technologies, such as single photon emitters, hybrid spin-photon interfaces, or spin-mechanics interfaces.