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arXiv · 2308.16291

Solid-State $\rm ^{229}Th$ Nuclear Laser with Two-Photon Pumping

Haowei Xu·Hao Tang·Guoqing Wang·Changhao Li·Boning Li·Paola Cappellaro·Ju Li
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Abstract

The radiative excitation of the 8.3 eV isomeric state of thorium-229 is an outstanding challenge due to the lack of tunable far-ultraviolet (F-UV) sources. In this work, we propose an efficient two-photon pumping scheme for thorium-229 using the optonuclear quadrupolar effect, which only requires a 300 nm UV-B pumping laser. We further demonstrate that population inversion between the nuclear isomeric and ground states can be achieved at room temperature using a two-step pumping process. The nuclear laser, which has been pursued for decades, may be realized using a Watt-level UV-B pumping laser and ultrawide bandgap thorium compounds (e.g., $\rm ThF_4$, $\rm Na_2ThF_6$, or $\rm K_2ThF_6$) as the gain medium.

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Haowei Xu, Hao Tang, Guoqing Wang, Changhao Li, Boning Li, Paola Cappellaro, Ju Li. 2023-08-30. Solid-State $\rm ^{229}Th$ Nuclear Laser with Two-Photon Pumping. https://doi.org/10.1103/physreva.108.l021502

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