Consistent Creation of Bright, Stable and Monochromatic Room Temperature Quantum Emitters in Hexagonal Boron Nitride

Quantum emitters (QE), also known as single photon emitters, are essential components of measurement-based quantum information science systems. The practical usage of QEs requires perfect purity, indistinguishability and high creation efficiency of single photons. Hexagonal boron nitride (hBN) has been found to be possible host for QEs and been extensively studied for QE creation as its large electronic band gap and optical phonon energy, in principle, allowing it to host room temperature QEs with excellent monochromaticity. Although significant efforts have been made to realize deterministic QE creation in hBN, most of the reported approaches resulted in QEs with broad emission wavelength distribution and inconsistent optical properties. In this presentation, the authors report a deterministic creation of QEs by applying masked-carbon-ion implantation on freestanding hBN flakes, where almost identical room temperature QEs (emission center wavelength = 590.7 ± 2.7 nm) were produced consistently with perfect monochromaticity (full width half maximum = 7.1 ±1.7 nm) and excellent brightness (maximum emission rate approaching 1MHz). The QEs created by our method also showed exceptional stability against optical excitation, where they survived 1 MW/cm² (532nm) laser excitation for hours with no observable degradation in emission rate. Our method provides a reliable platform for characterization and fabrication research, helping to reveal the origins of the QEs in hBN and favoring the practical application, especially the industrial-scale production of quantum technology.