Electron-Induced State Conversion in Diamond NV Centers Measured with Pump-Probe Cathodoluminescence Spectroscopy

Magdalena Solà-Garcia; Sophie Meuret; Toon Coenen; Albert Polman

doi:10.1021/acsphotonics.9b01463

Electron-Induced State Conversion in Diamond NV Centers Measured with Pump-Probe Cathodoluminescence Spectroscopy

ACS Photonics. 2020 Jan 15;7(1):232-240. doi: 10.1021/acsphotonics.9b01463. Epub 2019 Dec 2.

Authors

Magdalena Solà-Garcia¹, Sophie Meuret¹, Toon Coenen^{1

2}, Albert Polman¹

Affiliations

¹ Center for Nanophotonics, AMOLF, Science Park 104, 1098 XG, Amsterdam, The Netherlands.
² Delmic BV, Kanaalweg 4, 2628 EB, Delft, The Netherlands.

Abstract

Nitrogen-vacancy (NV) centers in diamond are reliable single-photon emitters, with applications in quantum technologies and metrology. Two charge states are known for NV centers, NV⁰ and NV^-, with the latter being mostly studied due to its long electron spin coherence time. Therefore, control over the charge state of the NV centers is essential. However, an understanding of the dynamics between the different states still remains challenging. Here, conversion from NV^- to NV⁰ due to electron-induced carrier generation is shown. Ultrafast pump-probe cathodoluminescence spectroscopy is presented for the first time, with electron pulses as pump and laser pulses as probe, to prepare and read out the NV states. The experimental data are explained with a model considering carrier dynamics (0.8 ns), NV⁰ spontaneous emission (20 ns), and NV⁰ → NV^- back transfer (500 ms). The results provide new insights into the NV^- → NV⁰ conversion dynamics and into the use of pump-probe cathodoluminescence as a nanoscale NV characterization tool.