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arXiv:2606.00748

Shortcut to Adiabatic Isomeric Population Transfer of the $^{229}\mathrm{Th}$ Nucleus via Hyperfine Electronic Bridge

Bo Liu, Wu Wang, Yong Li

quant-phSubmitted May 30, 2026• Announced Jun 2, 2026
arXivHTMLPDF

Abstract

The $^{229}$Th nucleus is well known for its exceptionally low-lying nuclear isomeric level, which provides a unique platform for exploring electron-nucleus interactions and gives rise to a variety of rich physical phenomena. One such phenomenon is the hyperfine electronic bridge, which has recently been shown to enable efficient and precise manipulation of the nuclear isomeric levels of $^{229}$Th [W. Wang $et~ al.$, Phys. Rev. Lett. \textbf{133}, 223001 (2024)]. However, that study used the stimulated Raman adiabatic passage method, which requires relatively long operation times. In this work, we employ the stimulated Raman shortcut-to-adiabatic passage method, which dramatically shortens the operation time from the order of hundreds of milliseconds to hundreds of microseconds while maintaining a transfer efficiency of about $79.38\%$.

Comments
10 pages, 4 figures

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Shortcut to Adiabatic Isomeric Population Transfer of the 229Th^{229}\mathrm{Th}229Th Nucleus via Hyperfine Electronic Bridge
The 229^{229}229Th nucleus is well known for its exceptionally low-lying nuclear isomeric level, which provides a unique platform for exploring electron-nucleus interactions and gives rise to a variety of rich physical phenomena. One such phenomenon is the hyperfine electronic bridge, which has recently been shown to enable efficient and precise manipulation of the nuclear isomeric levels of 229^{229}229Th [W. Wang et al.et~ al.et al., Phys. Rev. Lett. \textbf{133}, 223001 (2024)]. However, that study used the stimulated Raman adiabatic passage method, which requires relatively long operation times. In this work, we employ the stimulated Raman shortcut-to-adiabatic passage method, which dramatically shortens the operation time from the order of hundreds of milliseconds to hundreds of microseconds while maintaining a transfer efficiency of about 79.38%79.38\%79.38%.
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Nuclear coherent population transfer to the 229m^{229m}229mTh isomer using x-ray pulses
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