A solid-state nuclear clock based on the low-lying isomeric state in 229Th has attracted growing interest. One potential problem for the solid-state nuclear clock approach is the suitability of the doped environment for photon emission of the nuclear isomeric state. Specifically, Thn+ n < 4 ions could open non-radiative decay routes for deexcitation, hindering the photon emission. Here we have used time-resolved photoluminescence (TRPL) and density functional theory (DFT) calculations to characterize MgF2 crystals that have been implanted with 229Th recoils via a-decay from a 233U source with the goal of determining the charge state of the implanted thorium atoms. The DFT calculations predicted Th4+ to be the lowest energy oxidation state with Th3+ the next lowest in the MgF2 crystal environment. The DFT calculations also show Th4+:MgF2 system has a band gap large enough so that the internal electron conversion decay channel is suppressed. Experimentally, we found no evidence for thorium in oxidations state other than +4 using TRPL spectroscopy that has a detection limit for Thn+ n < 4 ions several orders of magnitude smaller than the number of implanted 229Th recoils. This work shows that the solid-state approach is a viable option for a nuclear clock.
| Published in | Science Journal of Chemistry (Volume 6, Issue 4) |
| DOI | 10.11648/j.sjc.20180604.15 |
| Page(s) | 66-76 |
| Creative Commons |
This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited. |
| Copyright |
Copyright © The Author(s), 2018. Published by Science Publishing Group |
229Th Isomeric State, Nuclear Clock, Optical Spectroscopy, Density Functional Theory, Thorium Doped MgF2 Crystal
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APA Style
Beau J. Barker, Edmund R. Meyer, Michael H. Schacht, Lee A. Collins, Marianne P. Wilkerson, et al. (2018). Oxidation State of 229Th Recoils Implanted into MgF2 Crystals. Science Journal of Chemistry, 6(4), 66-76. https://doi.org/10.11648/j.sjc.20180604.15
ACS Style
Beau J. Barker; Edmund R. Meyer; Michael H. Schacht; Lee A. Collins; Marianne P. Wilkerson, et al. Oxidation State of 229Th Recoils Implanted into MgF2 Crystals. Sci. J. Chem. 2018, 6(4), 66-76. doi: 10.11648/j.sjc.20180604.15
AMA Style
Beau J. Barker, Edmund R. Meyer, Michael H. Schacht, Lee A. Collins, Marianne P. Wilkerson, et al. Oxidation State of 229Th Recoils Implanted into MgF2 Crystals. Sci J Chem. 2018;6(4):66-76. doi: 10.11648/j.sjc.20180604.15
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Download@article{10.11648/j.sjc.20180604.15,
author = {Beau J. Barker and Edmund R. Meyer and Michael H. Schacht and Lee A. Collins and Marianne P. Wilkerson and Jason K. Ellis and Richard L. Martin and Xinxin Zhao},
title = {Oxidation State of 229Th Recoils Implanted into MgF2 Crystals},
journal = {Science Journal of Chemistry},
volume = {6},
number = {4},
pages = {66-76},
doi = {10.11648/j.sjc.20180604.15},
url = {https://doi.org/10.11648/j.sjc.20180604.15},
eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.sjc.20180604.15},
abstract = {A solid-state nuclear clock based on the low-lying isomeric state in 229Th has attracted growing interest. One potential problem for the solid-state nuclear clock approach is the suitability of the doped environment for photon emission of the nuclear isomeric state. Specifically, Thn+ n 2 crystals that have been implanted with 229Th recoils via a-decay from a 233U source with the goal of determining the charge state of the implanted thorium atoms. The DFT calculations predicted Th4+ to be the lowest energy oxidation state with Th3+ the next lowest in the MgF2 crystal environment. The DFT calculations also show Th4+:MgF2 system has a band gap large enough so that the internal electron conversion decay channel is suppressed. Experimentally, we found no evidence for thorium in oxidations state other than +4 using TRPL spectroscopy that has a detection limit for Thn+ n 229Th recoils. This work shows that the solid-state approach is a viable option for a nuclear clock.},
year = {2018}
}
TY - JOUR T1 - Oxidation State of 229Th Recoils Implanted into MgF2 Crystals AU - Beau J. Barker AU - Edmund R. Meyer AU - Michael H. Schacht AU - Lee A. Collins AU - Marianne P. Wilkerson AU - Jason K. Ellis AU - Richard L. Martin AU - Xinxin Zhao Y1 - 2018/10/31 PY - 2018 N1 - https://doi.org/10.11648/j.sjc.20180604.15 DO - 10.11648/j.sjc.20180604.15 T2 - Science Journal of Chemistry JF - Science Journal of Chemistry JO - Science Journal of Chemistry SP - 66 EP - 76 PB - Science Publishing Group SN - 2330-099X UR - https://doi.org/10.11648/j.sjc.20180604.15 AB - A solid-state nuclear clock based on the low-lying isomeric state in 229Th has attracted growing interest. One potential problem for the solid-state nuclear clock approach is the suitability of the doped environment for photon emission of the nuclear isomeric state. Specifically, Thn+ n 2 crystals that have been implanted with 229Th recoils via a-decay from a 233U source with the goal of determining the charge state of the implanted thorium atoms. The DFT calculations predicted Th4+ to be the lowest energy oxidation state with Th3+ the next lowest in the MgF2 crystal environment. The DFT calculations also show Th4+:MgF2 system has a band gap large enough so that the internal electron conversion decay channel is suppressed. Experimentally, we found no evidence for thorium in oxidations state other than +4 using TRPL spectroscopy that has a detection limit for Thn+ n 229Th recoils. This work shows that the solid-state approach is a viable option for a nuclear clock. VL - 6 IS - 4 ER -
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