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ACS Photonics

On-Demand Generation of Single Silicon Vacancy Defects in Silicon Carbide

Junfeng Wang, Qiang Li, Fei-Fei Yan, He Liu, Guo‐Ping Guo, Weiping Zhang, Xiong Zhou, Liping Guo, Zhi-Hai Lin, Jin‐Ming Cui, Xiao‐Ye Xu, Jin‐Shi Xu, Chuan‐Feng Li, Guang‐Can Guo

Published May 28, 2019• 96 citations

Abstract

Defects in silicon carbide have been explored as promising spin systems in quantum technologies. However, for practical quantum metrology and quantum communication, it is critical to achieve on-demand single spin-defect generation. In this work, we present the generation and characterization of shallow silicon vacancies in silicon carbide by using different implanted ions and annealing conditions. The conversion efficiency of a silicon vacancy of helium ions is shown to be higher than that by carbon and hydrogen ions in a wide implanted fluence range. Furthermore, after optimizing the annealing conditions, the conversion efficiency can be increased more than 2 times. Due to the high density of the generated ensemble defects, the sensitivity of sensing a static magnetic field can be reached as high as, which is about 9 times smaller than previous results. By carefully optimizing implanted conditions, we further show that a single silicon vacancy array can be generated with a high conversion efficiency of about 80%. The results pave the way for using an on-demand-generated single silicon vacancy for quantum information processing and quantum photonics.

DOI: 10.1021/acsphotonics.9b00451

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