Controlled generation of luminescent centers in hexagonal boron nitride by irradiation engineering

Abstract

Luminescent centers in the two-dimensional material hexagonal boron nitride have the potential to enable quantum applications at room temperature. To be used for applications, it is crucial to generate these centers in a controlled manner and to identify their microscopic nature. Here, we present a method inspired by irradiation engineering with oxygen atoms. We systematically explore the influence of the kinetic energy and the irradiation fluence on the generation of luminescent centers. We find modifications of their density for both parameters, while a fivefold enhancement is observed with increasing fluence. Molecular dynamics simulations clarify the generation mechanism of these centers and their microscopic nature. We infer that VNCB and VB− are the most likely centers formed. Ab initio calculations of their optical properties show excellent agreement with our experiments. Our methodology generates quantum emitters in a controlled manner and provides insights into their microscopic nature.

Atomistic Simulations of Defect Production in Monolayer and Bulk Hexagonal Boron Nitride under Low- and High-Fluence Ion Irradiation

“…Moreover, by choosing proper ion species and adjusting ion energies [ 24 ] and charge states [ 25 ], one can control the types of defects and their distribution in the sample. With regard to the creation and use of defects in quantum applications, ion beam mediated engineering of defects has indeed been demonstrated to be an effective tool to produce quantum emitters [ 3 , 10 , 13 ].…”

“…At the same time, impacts of energetic ions onto h-BN have received rather small amount of attention from theory. Irradiation of h-BN with oxygen ions [ 13 ] in a narrow energy range was addressed, and the response of single-layer h-BN to noble gas ion irradiation was also investigated [ 32 ]. Impacts of Xe ions onto multi-layer h-BN have also been simulated [ 33 ].…”

“…Hexagonal boron-nitride (h-BN) [8,9] has also received a considerable amount of attention in the context of defect-mediated optical response and potential applications in quantum technologies [10][11][12][13]. This material with a rather wide bandgap of 5.95 eV [14] has high mechanical and temperature stability and is usually used as a substrate due to its insulating properties and small surface roughness.…”

An ultrastable and robust single-photon emitter in hexagonal boron nitride

“…A single-photon emitter is a crucial component in building quantum information technologies, such as linear-optic quantum information processing [1], quantum simulation [2] and quantum communication [3]. Hexagonal boron nitride (hBN) is a two-dimensional (2D) material with a wide bandgap (∼6 eV) [4,5], and can host stable and bright color centers which possess singlephoton emission [6]. Meanwhile, the manipulation of the optoelectronic properties of singe-photon emitters has garnered special interest [7,8].…”

“…Theoretically, several defects have been proposed to be possibly responsible for single-photon emission, such as C B V N [6,36], boron dangling bonds [37], N B V N [38], and carbon trimers [39]. Based on experimental obser- vations [13], we focus on carbon defects in this work.…”