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arXiv · 1907.09095

Experimental and theoretical analysis of noise strength and environmental correlation time for ensembles of nitrogen-vacancy centers in diamond

Kan Hayashi·Yuichiro Matsuzaki·Takaki Ashida·Shinobu Onoda·Hiroshi Abe·Takeshi Ohshima·Mutsuko Hatano·Takashi Taniguchi·Hiroki Morishita·Masanori Fujiwara·Norikazu Mizuochi
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Abstract

We experimentally and theoretically investigate the Hahn echo decay curve for nitrogen vacancy centers in diamond with different spin concentrations. The Hahn echo results show a non-exponential decay for low spin concentrations, while an exponential decay is dominant for high spin concentrations. By fitting the decay curve with a theoretical model, we show that both the amplitude and correlation time of the environmental noise have a clear dependence on the spin concentration. These results are essential for optimizing the NV center concentration in high-performance quantum devices, particularly quantum sensors.

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Kan Hayashi, Yuichiro Matsuzaki, Takaki Ashida, Shinobu Onoda, Hiroshi Abe, Takeshi Ohshima, Mutsuko Hatano, Takashi Taniguchi, Hiroki Morishita, Masanori Fujiwara, Norikazu Mizuochi. 2019-09-17. Experimental and theoretical analysis of noise strength and environmental correlation time for ensembles of nitrogen-vacancy centers in diamond. https://doi.org/10.7566/jpsj.89.054708

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