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arXiv · 2209.08505

Maskless Generation of Single Silicon Vacancy Arrays in Silicon Carbide by a Focused He+ Ion Beam

Abstract

Precise generation of spin defects in solid-state systems is essential for nanostructure fluorescence enhancement. We investigated a method for creating single silicon vacancy defect arrays in silicon carbide using a helium-ion microscope. Maskless and targeted generation can be realized by precisely controlling the focused He+ ion beam with an implantation uncertainty of 60 nm. The generated silicon vacancies were identified by measuring the optically detected magnetic resonance spectrum and room temperature photoluminescence spectrum. We systematically studied the effects of the implantation ion dose on the generated silicon vacancies. After optimization, a conversion yield of ~ 6.95 % and a generation rate for a single silicon vacancy of ~ 35 % were realized. This work paves the way for the integration and engineering of color centers to photonic structures and the application of quantum sensing based on spin defects in silicon carbide.

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Zhen-Xuan He, Qiang Li, Xiao-Lei Wen, Ji-Yang Zhou, Wu-Xi Lin, Zhi-He Hao, Jin-Shi Xu, Chuan-Feng Li, Guang-Can Guo. 2022-09-18. Maskless Generation of Single Silicon Vacancy Arrays in Silicon Carbide by a Focused He+ Ion Beam. https://doi.org/10.1021/acsphotonics.2c01209

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