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arXiv · 1707.04702

Extension of the Coherence Time by Generating MW Dressed States in a Single NV Centre in Diamond

Hiroki Morishita·Toshiyuki Tashima·Disuke Mima·Hiromitsu Kato·Toshiharu Makino·Satoshi Yamasaki·Masanori Fujiwara·Norikazu Mizuochi
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Abstract

Nitrogen-vacancy (NV) centres in diamond hold promise in quantum sensing applications. A major interest in them is an enhancement of their sensitivity by the extension of the coherence time ($T_2$). In this report, we experimentally generated more than four dressed states in a single NV centre in diamond based on Autler-Townes splitting (ATS). We also observed the extension of the coherence time to $T_2 \sim$ 1.5 ms which is more than two orders of magnitude longer than that of the undressed states. As an example of a quantum application using these results we propose a protocol of quantum sensing, which shows more than an order of magnitude enhancement in the sensitivity.

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Hiroki Morishita, Toshiyuki Tashima, Disuke Mima, Hiromitsu Kato, Toshiharu Makino, Satoshi Yamasaki, Masanori Fujiwara, Norikazu Mizuochi. 2017-07-15. Extension of the Coherence Time by Generating MW Dressed States in a Single NV Centre in Diamond. https://arxiv.org/abs/1707.04702

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