Deterministic activation of room-temperature quantum emitter arrays in hexagonal boron nitride*

Defects in hexagonal boron nitride (hBN) have recently been shown to exhibit narrow linewidth, room temperature single photon emission (SPE) which make them highly attractive for quantum technologies. However, the difficulty in control of defect formation in hBN both spectrally and spatially has been a major hurdle in further development of these SPEs for quantum technologies. Here, we demonstrate nanoscale spatial control of emitter formation in hBN through strain engineering. Our approach relies on placing the few-layer hBN film on top of a patterned substrate consisting of SiO₂ nanopillars. Once transferred, the hBN drapes over the silica pillar, creating a tent-like structure where the hBN exhibits preferential quantum emission localized to the pillar edges where the hBN is subjected to large strains. The spatial control of emission and spectral homogeneity of the SPEs in hBN at room temperature offers a route forward for salable integarted quantum photonic systems and on-demand deterministic room temperature quantum emitters.