Quantum emitters are pivotal in advancing quantum technologies and their leveraging properties allow the emission of single photons essential for quantum computing, secure communications, and high-sensitivity sensing. Our research involves the development of these quantum emitters through the innovative use of two-dimensional (2D) materials, such as transition metal dichalcogenides (MoS₂, WSe₂). The goal is to surpass traditional 3D quantum emitter’s limitations, enhancing integration capabilities and operational efficiency in quantum technology applications. The primary method involves the generation of optically active and deterministic defects that cause minimal lattice damage by employing ultralow-energy electron irradiation within these 2D materials. This precision ensures the optimal positioning of quantum emitters within the material and maintains the integrity of the host material’s structure. Furthermore, our work focuses on integrating these quantum emitters with small mode-volume optical cavities, achieving significant enhancements in their brightness which is crucial for improving quantum communication efficiency, particularly in quantum key distribution, and propels the capabilities of quantum sensing technologies forward. Despite various advancements, challenges remain in optimising the performance and integration of quantum emitters for practical applications. Our ongoing research is focused on overcoming these hurdles and pushing the boundaries of the fabrication of quantum emitters.

Useful references
Ajit Kumar Dash et al., “Evidence of defect formation in monolayer MoS2 at ultralow accelerating voltage electron irradiation”, 2D Mater. 10 035002 (2023)
Ajit Kumar Dash et al., “Effect of electron-irradiation on layered quantum materials”, Bulletin of Mater. Sci., Vol. 44, 227, (2021)
Ajit Kumar Dash et al., “Quantum light generation with ultra-high spatial resolution in 2D semiconductors via ultra-low energy electron irradiation.” arXiv preprint arXiv:2409.10321 (2024).
Turunen et al., “Quantum photonics with layered 2D materials”, Nat. Rev. Phy. Vol. 4, 219–236, (2022)