Nuclear excitation of the ${}^{229}$Th isomer via defect states in doped crystals

Abstract

When Th nuclei are doped in CaF${}_2$ crystals, a set of electronic defect states appears in the crystal bandgap which would otherwise provide complete transparency to vacuum-ultraviolet radiation. The coupling of these defect states to the 8 eV ${}^{229m}$Th nuclear isomer in the CaF${}_2$ crystal is investigated theoretically. We show that although previously viewed as a nuisance, the defect states provide a starting point for nuclear excitation via electronic bridge mechanisms involving stimulated emission or absorption using an optical laser. The rates of these processes are at least two orders of magnitude larger than direct photoexcitation of the isomeric state using available light sources. The nuclear isomer population can also undergo quenching when triggered by the reverse mechanism, leading to a fast and controlled decay via the electronic shell. These findings are relevant for a possible solid-state nuclear clock based on the ${}^{229m}$Th isomeric transition.

References in corpus (8)

• Direct detection of the 229Th nuclear clock transition
• Enhanced effect of temporal variation of the fine structure constant in diatomic molecules
• Proposal for a Nuclear Gamma-Ray Laser of Optical Range
• Performance of a 229 Thorium solid-state nuclear clock
• Excitation of the isomeric ^{229m}Th nuclear state via an electronic bridge process in ^{229}Th^+
• Nuclear clocks based on resonant excitation of gamma-transitions
• Electronic bridge excitation in highly charged Th-229 ions
• Results of a direct search using synchrotron radiation for the low-energy ${}^{229}$Th nuclear isomeric transition

Cited by in corpus (9)

• Sensitivity of ${}^{229}$Th nuclear clock transition to variation of the fine-structure constant
• The ${}^{229}$Th isomer: prospects for a nuclear optical clock
• Expanding Nuclear Physics Horizons with the Gamma Factory
• Recollision induced nuclear excitation of ${}^{229}$Th
• Driven electronic bridge processes via defect states in ${}^{229}$Th-doped crystals
• Optical Transmission Enhancement of Ionic Crystals via Superionic Fluoride Transfer: Growing VUV-Transparent Radioactive Crystals
• Solid-State ${}^{229}\mathrm{Th}$ Nuclear Laser with Two-Photon Pumping
• Proposal for a Nuclear Light Source
• Isomer depletion via nuclear excitation by inelastic electron scattering