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arXiv · 2411.17187

Quantum Orbital-State Control of a Neutral Nitrogen-Vacancy Center at Millikelvin Temperatures

Hodaka Kurokawa·Shintaro Nakazato·Toshiharu Makino·Hiromitsu Kato·Shinobu Onoda·Yuhei Sekiguchi·Hideo Kosaka
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Abstract

A neutral nitrogen-vacancy center (NV$^0$) is promising for realizing strong coupling with a single microwave photon due to its large electric field sensitivity, although it is susceptible to environmental phonon noise at 5 K. Decreasing the temperature to 15 mK results in a tenfold increase in orbital relaxation time compared to that at 5 K. Dynamical decoupling pulses significantly increase the orbital coherence time to around 1.8 $\mu$s, representing a 30-fold improvement compared to that without decoupling pulses. Based on these results, a single NV$^0$ can reach the strong coupling regime when coupled with a high-impedance microwave resonator, thus opening up the possibility of microwave quantum electrodynamics using a single optically-active defect center in diamond.

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Hodaka Kurokawa, Shintaro Nakazato, Toshiharu Makino, Hiromitsu Kato, Shinobu Onoda, Yuhei Sekiguchi, Hideo Kosaka. 2024-11-26. Quantum Orbital-State Control of a Neutral Nitrogen-Vacancy Center at Millikelvin Temperatures. https://doi.org/10.1103/m1qx-xlpd

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