The energetic disorder induced by fluctuating liquid environments acts in opposition to the precise control required for coherence-based sensing. Overcoming fluctuations requires a protected quantum subspace that only weakly interacts with the local environment. We report a ytterbium complex that exhibited an ultranarrow absorption linewidth in solution at room temperature with a full width at half maximum of 0.625 milli–electron volts. Using spectral hole burning, we measured an even narrower linewidth of 410 pico–electron volts at 77 kelvin. Narrow linewidths allowed low-field magnetic circular dichroism at room temperature, used to sense Earth-scale magnetic fields. These results demonstrated that ligand protection in lanthanide complexes could substantially diminish electronic state fluctuations. We have termed this system an “atomlike molecular sensor” (ALMS) and proposed approaches to improve its performance.

中文翻译：

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面向液体细胞量子传感：具有超窄吸收的镱配合物


由波动的液体环境引起的能量紊乱与基于相干传感所需的精确控制相反。克服波动需要一个受保护的量子子空间，该子空间仅与局部环境微弱相互作用。我们报道了一种镱络合物，该络合物在室温下在溶液中表现出超窄吸收线宽，半峰全宽为 0.625 毫电子伏。使用光谱烧孔，我们在 77 开尔文下测量了 410 皮电子伏特的更窄线宽。窄线宽允许在室温下实现低场磁圆二色性，用于感测地球尺度的磁场。这些结果表明，镧系元素配合物中的配体保护可以显着减少电子态波动。我们将该系统称为“类原子分子传感器”（ALMS），并提出了提高其性能的方法。