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arXiv · 2411.15641

Theory of internal conversion of the thorium-229 nuclear isomer in solid-state hosts

H. W. T. Morgan·H. B. Tran Tan·R. Elwell·A. N. Alexandrova·Eric R. Hudson·Andrei Derevianko
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Abstract

Laser excitation of thorium-229 nuclei in doped wide bandgap crystals has been demonstrated recently, opening the possibility of developing ultrastable solid-state clocks and sensitive searches for new physics. We develop a quantitative theory of the internal conversion of isomeric thorium-229 in solid-state hosts. The internal conversion of the isomer proceeds by resonantly exciting a valence band electron to a defect state, accompanied by multi-phonon emission. We demonstrate that, if the process is energetically allowed, it generally quenches the isomer on timescales much faster than the isomer's radiative lifetime, despite thorium being in the +4 charge state in the valence band.

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H. W. T. Morgan, H. B. Tran Tan, R. Elwell, A. N. Alexandrova, Eric R. Hudson, Andrei Derevianko. 2024-11-23. Theory of internal conversion of the thorium-229 nuclear isomer in solid-state hosts. https://doi.org/10.1103/9s8f-hv1f

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