钍-229 作为声子磁力计
Thorium-229 as a Phonomagnetometer
- Wolfgang Pauli Institute（沃尔夫冈·泡利研究所）
- Institute for Theoretical Physics, TU Wien（维也纳工业大学理论物理研究所）
- Institute for Atomic and Subatomic Physics, TU Wien（维也纳工业大学原子与亚原子物理研究所）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本文提出将钍-229 掺杂进固态基质以探测声子磁场，评估了 Na$_2$ThF$_6$ 作为基质材料，并模拟了两种激发方案，发现圆偏振激光方案可能达到探测阈值，为声子磁测量提供了可行路径。
AI中文摘要：
钍-229 拥有唯一已知的、适用于窄带 VUV 激光光谱学的低能核跃迁。虽然之前的实验侧重于将其用作核钟，但该跃迁也为高精度磁测量提供了一条途径。关于携带角动量的声子所产生的磁场的实验观测仍无定论，这凸显了对潜在物理机制进行定量检验的必要性。在本文中，我们提出将钍-229 掺杂到固态基质中，以原位探测声子磁场。我们确定了 Na$_2$ThF$_6$（一种手性化学计量钍化合物）作为有前景的基质材料，并评估了其在两种激发方案下对磁相互作用的谱学灵敏度：用圆偏振激光驱动简并声子模式，以及施加温度梯度。密度泛函理论模拟结合定量估算表明，温度梯度方案产生的磁信号似乎太弱而无法测量，而圆偏振、高强度 THz/VUV 泵浦-探测驱动的声子磁响应可能接近散粒噪声限制的探测阈值。尽管实验挑战依然存在，钍-229 的独特适用性为在固态平台上探测声子磁场提供了一条可测试的途径。
英文摘要：
Thorium-229 possesses the only known low-energy nuclear transition suitable for spectroscopy with narrowband VUV lasers. While previous experiments have focused on application as a nuclear clock, this transition also offers a route to high-accuracy magnetometry. Experimental observations of magnetic fields generated by phonons carrying angular momentum remain inconclusive, highlighting the need for quantitative tests of the underlying physical mechanisms. In this article, we propose doping thorium-229 into a solid-state host to probe phonomagnetic fields in situ. We identify Na$_2$ThF$_6$, a chiral stoichiometric thorium compound, as a promising host material and evaluate its spectroscopic sensitivity to magnetic interactions under two excitation schemes: driving degenerate phonon modes with a circularly polarized laser, and applying a temperature gradient. Density functional theory simulations combined with quantitative estimates suggest that the temperature-gradient scheme yields a magnetic signal that appears too weak to be measurable, while a circularly polarized, high-intensity THz/VUV pump-probe driven phonomagnetic response may approach the shot-noise-limited detection threshold. While experimental challenges remain, the unique suitability of thorium-229 provides a testable pathway toward detecting phonomagnetic fields in a solid-state platform.
