Deterministic generation of single B centers in hBN by one-to-one conversion from UV centers

TL;DR

This study introduces an in-situ cathodoluminescence method to precisely activate and deactivate individual B centers in hBN, enabling deterministic creation of single quantum emitters for photonic applications.

Contribution

The paper presents a novel real-time monitoring technique for controlled activation of B centers in hBN, advancing deterministic quantum emitter integration.

Findings

Activation of B centers correlates with deactivation of UV centers.

Controlled creation of single emitters at specific sites.

Technique allows for selective deactivation of individual emitters.

Abstract

Among the variety of quantum emitters in hexagonal boron nitride (hBN), blue-emitting color centers, or B centers, have gathered a particular interest owing to their excellent quantum optical properties. Moreover, the fact that they can be locally activated by an electron beam makes them suitable for top-down integration in photonic devices. However, in the absence of a real-time monitoring technique sensitive to individual emitters, the activation process is stochastic in the number of emitters, and its mechanism is under debate. Here, we implement an in-situ cathodoluminescence monitoring setup capable of detecting individual quantum emitters in the blue and ultraviolet (UV) range. We demonstrate that the activation of individual B centers is spatially and temporally correlated with the deactivation of individual UV centers emitting at 4.1 eV, which are ubiquitous in hBN. We then make use of the ability to detect individual B center activation events to demonstrate the controlled creation of an array with only one emitter per irradiation site. Additionally, we demonstrate a symmetric technique for heralded selective deactivation of individual emitters. Our results provide insights into the microscopic structure and activation mechanism of B centers, as well as versatile techniques for their deterministic integration.