Non-destructive state detection for quantum logic spectroscopy of molecular ions
Non-destructive state detection for quantum logic spectroscopy of molecular ions
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DOI：
10.1038/nature16513
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发表时间：
2015-07
期刊：
影响因子：
64.8
通讯作者：
F. Wolf;Y. Wan;J. C. Heip;F. Gebert;Chunyan Shi;P. Schmidt
中科院分区：
文献类型：
--
作者：
F. Wolf;Y. Wan;J. C. Heip;F. Gebert;Chunyan Shi;P. Schmidt
冷态分子离子的精确激光光谱学是基础物理学中的一个强有力的工具，例如，用于确定基本常数，在实验室中测试它们可能的变化，以及寻找电子的可能的电偶极矩。然而，分子中缺乏循环跃迁对离子的直接激光冷却和控制提出了挑战。并检测它们的量子态。以前使用的基于光解离或化学反应的状态检测技术是破坏性的，因此效率低下，限制了激光光谱学中可实现的分辨率。在这里，我们实验证明了非破坏性检测的量子态的一个单一的被困分子离子通过其强库仑耦合到一个控制良好，共同捕获的原子离子。一种基于状态相关光学偶极力的算法根据分子的内部状态改变原子的内部状态。我们表明，在分子离子中的各个量子态可以区分其耦合到光偶极力的强度。我们还观察到量子跳跃（黑体辐射诱导）之间的旋转状态的一个单一的分子离子。使用状态检测信号的失谐依赖性，我们实现了量子逻辑光谱学的一个变体，分子共振。我们的状态检测技术与广泛的分子离子有关，并可应用于状态控制的量子化学和作为星际云探针的分子的光谱研究。
Precision laser spectroscopy of cold and trapped molecular ions is a powerful tool in fundamental physics—used, for example, in determining fundamental constants, testing for their possible variation in the laboratory,, and searching for a possible electric dipole moment of the electron. However, the absence of cycling transitions in molecules poses a challenge for direct laser cooling of the ions, and for controlling,,,,and detecting their quantum states. Previously used state-detection techniques based on photodissociation or chemical reactions are destructive and therefore inefficient, restricting the achievable resolution in laser spectroscopy. Here, we experimentally demonstrate non-destructive detection of the quantum state of a single trapped molecular ion through its strong Coulomb coupling to a well controlled, co-trapped atomic ion. An algorithm based on a state-dependent optical dipole force changes the internal state of the atom according to the internal state of the molecule. We show that individual quantum states in the molecular ion can be distinguished by the strength of their coupling to the optical dipole force. We also observe quantum jumps (induced by black-body radiation) between rotational states of a single molecular ion. Using the detuning dependence of the state-detection signal, we implement a variant of quantum logic spectroscopy,of a molecular resonance. Our state-detection technique is relevant to a wide range of molecular ions, and could be applied to state-controlled quantum chemistry and to spectroscopic investigations of molecules that serve as probes for interstellar clouds,.