18Fig. 2. The Purcell factor of an hBN CC with a fixed emission wavelength of λ=804 nm and varying the CC/NP separation distance. References 1) V. Karanikolas, S. Suzuki, S. Li, T. Iwasaki, Appl. Phys. Lett. 120, 040501 (2022). 2) V. Karanikolas, T. Iwasaki, J. Henzie, N. Ikeda, Y. Yamauchi, Y. Wakayama, T. Kuroda, K. Watanabe, T. Taniguchi, ACS Omega 8, 14641 (2023).Fig. 1. Comparison between the emission decay curves for the hBN:C layer on the Ag NPs (red circles) and the SiO2 substrate (broken line). The decay curves are normalized to their peak intensity. The gray shade indicates the instrumental response function.components hBN is a wide band-gap (~6 eV) material that can host myriad emission centers with different resonance wavelengths. The exact nature and properties of the various defects are under theoretical investigation. We use carbon-enriched hBN (hBN:C), which possesses numerous optical emission peaks spanning the visible and near-infrared parts of the EM spectrum. Among the different emission centers of the hBN:C, the atom-like color-center (CC) defect emission, with resonance wavelength at 804 nm, is significant because of its strong intensity up to room temperatures. The CCs of the hBN:C bulk crystal are already high-quality photon sources, with a lifetime of around 350 ps. We further accelerate the relaxation of the CC to below 50 ps, by placing them close to Ag nanoparticles (NPs), see Figure 1. The near-filed of the CC excites the plasmon mode of the Ag triangle NPs. The accelerated relaxation of the CCs gives a Purcell factor of 8. Research Digest quantum for theoretical techniques The CCs are hosted to a hBN layer of thickness of 26 nm and their emission spectrum cannot be detected. Once they are coupled to the Ag NPs their emission is easily measured. Thus, we fabricated an ultra-fast and ultra-bright quantum photon source [2].In Figure 2 we theoretically analyze the Purcell factor of the CCs through numerical simulations. Good agreement is observed between the experimentally extracted values and the simulations. 1. Outline of ResearchUnderstanding light-matter interactions at the nanoscale is essential for developing the next-generation photonic and optoelectronic computing, communication and sensing applications. Two-dimensional (2D) materials have been explored experimentally and theoretically as nanophotonic building blocks because they possess better optical and mechanical properties than conventional dielectric and noble metal materials. I use state-of-the-art numerical and to perform numerical experiments to design quantum applications based on 2D materials [1].2. Research ActivitiesQuantum 2D MaterialsVasileios KARANIKOLAS
元のページ ../index.html#20