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arXiv · 2301.10383

Spectroscopy of photoionization from the $^1E$ singlet state in nitrogen$-$vacancy centers in diamond

Sean M. Blakley·Thuc T. Mai·Stephen J. Moxim·Jason T. Ryan·Adam J. Biacchi·Angela R. Hight Walker·Robert D. McMichael
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Abstract

The $^1E-^1A_1$ singlet manifold of the negatively charged nitrogen vacancy $(NV^-)$ center in diamond plays a central role in the quantum information and quantum sensing applications of the $NV^-$ center. However, the energy of this manifold within the diamond bandgap and with respect to the $^3A_2-^3E$ triplet manifold has not been measured directly. Using field-quenching effects on photoluminescence (PL) spectra, we report on the energy gap between the $^1E-^1A_1$ singlet manifold and the $^3A_2$ and $^3E$ ground and excited triplet states of the $NV^-$ as a function of excitation wavelength and power, temperature, and applied magnetic field in a heavily nitrogen-doped sample. Increased PL and decreased zero-phonon line width from the $NV^0$ were observed in the presence of an applied magnetic field, indicating ionization from the long-lived $^1E$ singlet state. A temperature-dependent ionization threshold between 532 nm and 550 nm was found, locating the singlet states within the diamond band gap.

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Sean M. Blakley, Thuc T. Mai, Stephen J. Moxim, Jason T. Ryan, Adam J. Biacchi, Angela R. Hight Walker, Robert D. McMichael. 2023-01-25. Spectroscopy of photoionization from the $^1E$ singlet state in nitrogen$-$vacancy centers in diamond. https://arxiv.org/abs/2301.10383

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