Wide-field spectral super-resolution mapping of optically active defects in hBN

TL;DR

This paper demonstrates a wide-field spectral super-resolution microscopy technique to analyze and map optically active defects in hBN, revealing defect heterogeneity and dynamics at the single-molecule level.

Contribution

It introduces a novel wide-field spectral SMLM method for detailed defect characterization in hBN, enabling multidimensional mapping of defect properties.

Findings

Identified at least two defect types in CVD-grown hBN.

Irradiated exfoliated flakes show predominantly one defect type.

Analyzed blinking kinetics and spectral emission of defects.

Abstract

Point defects can have significant impacts on the mechanical, electronic and optical properties of materials. The development of robust, multidimensional, high-throughput and large-scale characterization techniques of defects is thus crucial, from the establishment of integrated nanophotonic technologies to material growth optimization. Here, we demonstrate the potential of wide-field spectral single-molecule localization microscopy (spectral SMLM) for the determination of ensemble spectral properties, as well as characterization of spatial, spectral and temporal dynamics of single defects in CVD-grown and irradiated exfoliated hexagonal boron-nitride (hBN) materials. We characterize the heterogeneous spectral response of our samples, and identify at least two types of defects in CVD-grown materials, while irradiated exfoliated flakes show predominantly only one type of defect. We analyze the blinking kinetics and spectral emission for each type of defects, and discuss their implications with respect to the observed spectral heterogeneity of our samples. Our study shows the potential of wide-field spectral SMLM techniques in material science and paves the way towards quantitative multidimensional mapping of defect properties.