2023/06/27 by Nadezda Varkentina, Varkentina, Nadezda, Yves Auad +21
Earth and Planetary Sciences · Materials Science · #Diamond and Carbon-based Materials Research #Electronic and Structural Properties of Oxides #FOS: Physical sciences #High-pressure geophysics and materials #Materials Science (cond-mat.mtrl-sci)
paper · pdf · doi:10.48550/arxiv.2306.15372
openalex publication_date 2023/06/27 · openalex created_date 2023/06/29 · openalex updated_date 2026/07/28
Electron-photon temporal correlations in electron energy loss (EELS) and cathodoluminescence (CL) spectroscopies have recently been used to measure the relative quantum efficiency of materials. This combined spectroscopy, named Cathodoluminescence excitation spectroscopy (CLE), allows the identification of excitation and decay channels which are hidden in average measurements. Here, we demonstrate that CLE can also be used to measure excitation's decay time. In addition, the decay time as a function of the excitation energy is accessed, as the energy for each electron-photon pair is probed. We used two well-known insulating materials to characterize this technique, nanodiamonds with NV0 defect emission and h-BN with a 4.1 eV defect emission. Both also exhibit marked transition radiations, whose extremely short decay times can be used to characterize the instrumental response function. It is found to be typically 2 ns, in agreement with the expected limit of the EELS detector temporal resolution. The measured lifetimes of NV0 centers in diamond nanoparticles (20 to 40 ns) and 4.1 eV defect in h-BN flakes (< 2 ns) matches those reported for those materials previously.