Resonant Excitation of Quantum Emitters in Hexagonal Boron Nitride

Quantum emitters in layered hexagonal boron nitride (hBN) have recently attracted a great attention as promising single photon sources. In this work, we demonstrate resonant excitation of a single defect center in hBN, one of the most important prerequisites for employment of optical sources in quantum information application. We observe spectral linewidths of hBN emitter narrower than 1 GHz while the emitter experiences spectral diffusion. Temporal photoluminescence measurements reveals an average spectral diffusion time of around 100 ms. On-resonance photon antibunching measurement is also realized. Our results shed light on the potential use of quantum emitters from hBN in nanophotonics and quantum information

Framework for engineering of spin defects in hexagonal boron nitride by focused ion beams

Hexagonal boron nitride (hBN) is gaining interest as a wide bandgap van der Waals host of optically active spin defects for quantum technologies. Most studies of the spin-photon interface in hBN focus on the negatively charged boron vacancy (VB-) defect, which is typically fabricated by ion irradiation. However, VB- fabrication methods often lack robustness and reproducibility when applied to thin flakes (less than 10 nm) of hBN. Here we identify mechanisms that both promote and inhibit VB- generation and optimize ion beam parameters for site-specific fabrication of optically active VB- centers. We emphasize conditions accessible by high resolution focused ion beam (FIB) systems, and present a framework for VB- fabrication in hBN flakes of arbitrary thickness for applications in quantum sensing and quantum information processing.Comment: 11 pages, 5 figure

Near‐Field Energy Transfer between a Luminescent 2D Material and Color Centers in Diamond

Energy transfer between fluorescent probes lies at the heart of many applications ranging from bio‐sensing and bio‐imaging to enhanced photodetection and light harvesting. In this work, Förster resonance energy transfer (FRET) between shallow defects in diamond—nitrogen‐vacancy (NV) centers—and atomically thin, 2D materials—tungsten diselenide (WSe2)—is studied. By means of fluorescence lifetime imaging, the occurrence of FRET in the WSe2/NV system is demonstrated. Further, it is shown that in the coupled system, NV centers provide an additional excitation pathway for WSe2 photoluminescence. The results constitute the first step toward the realization of hybrid quantum systems involving single‐crystal diamond and 2D materials that may lead to new strategies for studying and controlling spin transfer phenomena and spin valley physics

Near‐Field Energy Transfer between a Luminescent 2D Material and Color Centers in Diamond

Energy transfer between fluorescent probes lies at the heart of many applications ranging from bio‐sensing and bio‐imaging to enhanced photodetection and light harvesting. In this work, Förster resonance energy transfer (FRET) between shallow defects in diamond—nitrogen‐vacancy (NV) centers—and atomically thin, 2D materials—tungsten diselenide (WSe2)—is studied. By means of fluorescence lifetime imaging, the occurrence of FRET in the WSe2/NV system is demonstrated. Further, it is shown that in the coupled system, NV centers provide an additional excitation pathway for WSe2 photoluminescence. The results constitute the first step toward the realization of hybrid quantum systems involving single‐crystal diamond and 2D materials that may lead to new strategies for studying and controlling spin transfer phenomena and spin valley physics