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arXiv · 2206.09047

Zeeman-Hyperfine Measurements of a Pseudo-Degenerate Quadruplet in CaF$_2$:Ho$^{3+}$

Kieran M. Smith·Michael F. Reid·Jon-Paul R. Wells
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Abstract

We report Zeeman infra-red spectroscopy of electronic-nuclear levels of $^5$I$_8 \rightarrow ^5$I$_7$ transitions of Ho$^{3+}$ in the C$_{\rm 4v}$(F$^-$) centre in CaF$_2$ with the magnetic field along the $\langle 111\rangle$ direction of the crystal. Transitions to the lowest $^5$I$_7$ state, an isolated electronic doublet, and the next group of states, a pseudo-quadruplet consisting of a doublet and two nearby singlets, exhibit strongly non-linear Zeeman splittings and intensity variations. Simulated spectra based upon a crystal-field analysis give an excellent approximation to the data, illustrating the strong predictive ability of the parametrised crystal-field approach. Anti-crossings in the hyperfine splittings, the basis of quantum information storage in rare-earth doped insulating dielectrics, are also predicted.

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Kieran M. Smith, Michael F. Reid, Jon-Paul R. Wells. 2022-06-17. Zeeman-Hyperfine Measurements of a Pseudo-Degenerate Quadruplet in CaF$_2$:Ho$^{3+}$. https://doi.org/10.1134/s0030400x23020200

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