# Laser direct writing and Raman Stokes contrast screening of quantum emitter sites in hBN

## TL;DR

Researchers developed a new method to quickly identify and map quantum emitter sites in hBN using laser writing and Raman spectroscopy, improving the efficiency of quantum nanophotonics.

## Contribution

A streamlined workflow combining laser direct writing and Raman Stokes contrast screening for rapid localization of quantum emitters in hBN.

## Key findings

- Quantum emitters emerge with minimal lattice modification, correlating with PL hotspots.
- Localized compressive strain surrounds emission sites, revealed through micro-Raman mapping.
- Two defect families with distinct emission ranges and vibronic coupling characteristics were identified.

## Abstract

Laser direct writing (LDW) enables the spatially defined creation of room-temperature single-photon emitters (SPEs) in hexagonal boron nitride (hBN). However, the rapid characterization of written sites remains a bottleneck, and the available toolset for efficient screening is limited. Here, we demonstrate a streamlined LDW workflow utilizing single-shot pulses combined with a confocal screening technique that exploits the hBN E2g​ Stokes line to rapidly localize and map laser-modified regions without relying a priori on defect photoluminescence (PL). This approach enables the direct correlation of site morphology with PL hotspots, revealing that the emergence of single-photon emitters coincides with a threshold regime of minimal lattice modification. Micro-Raman spectral mapping further uncovers localized compressive strain surrounding these emission sites. We classify the generated defects into two families: narrowband “red” emitters (650–750 nm) with weak phonon sidebands (PSB), and 600–650 nm emitters with stronger vibronic coupling, both exhibiting linear polarization and high single-photon purity. These results establish a practical protocol for rapid prototyping, offering a valuable addition to the characterization toolkit for scalable quantum nanophotonics.

The online version contains supplementary material available at 10.1186/s11671-026-04530-9.