Blue-Light-Emitting Color Centers in High-Quality Hexagonal Boron Nitride

TL;DR

This paper reports the discovery of a new blue-light-emitting color center in high-quality hexagonal boron nitride, which can be controlled by electron beam irradiation, and has potential applications in quantum technologies.

Contribution

The study identifies a novel color center in ultra-high-quality h-BN with unique spectral properties, linked to specific synthetic conditions, expanding the understanding of defect-based quantum emitters.

Findings

New color center at 435 nm in h-BN identified

Emitters are activated/deactivated by electron beam irradiation

Unique to high-quality h-BN grown with specific methods

Abstract

Light emitters in wide band gap semiconductors are of great fundamental interest and have potential as optically addressable qubits. Here we describe the discovery of a new color center in high-quality hexagonal boron nitride (h-BN) with a sharp emission line at 435 nm. The emitters are activated and deactivated by electron beam irradiation and have spectral and temporal characteristics consistent with atomic color centers weakly coupled to lattice vibrations. The emitters are conspicuously absent from commercially available h-BN and are only present in ultra-high-quality h-BN grown using a high-pressure, high-temperature Ba-B-N flux/solvent, suggesting that these emitters originate from impurities or related defects specific to this unique synthetic route. Our results imply that the light emission is activated and deactivated by electron beam manipulation of the charge state of an impurity-defect complex.