论文标题
脉冲量子光谱的基本限制：偶极矩估计
Fundamental limits of pulsed quantum light spectroscopy: Dipole moment estimation
论文作者
论文摘要
我们研究量子系统估计参数估计参数精确度的基本限制，当时它是通过量子光的行进脉冲探测的。特别是，我们专注于脉冲和两级原子之间相互作用强度的估计，相当于偶极矩的估计。我们对单光子脉冲的分析突出了通过在吸收光谱中测量的原子吸收的信息以及由于自发发射而引起的光子时间模式的相互作用之间的相互作用。除了单光子制度之外，我们还引入了一个近似模型，以在短脉冲的极限下研究更一般的光状态，在该脉冲的极限中，可以忽略自发发射。我们还表明，对于一类巨大的纠缠二光子状态，信号模式与原子相互作用和iDler模式之间的量子纠缠没有基本优势，并且可以通过可分离的状态获得相同的精度。我们通过研究使用量子光研究钠原子的电偶极矩的估计来结束。我们的工作启动了量子信息理论方法，用于开发量子光谱的理论和实践。
We study the fundamental limits of the precision of estimating parameters of a quantum matter system when it is probed by a travelling pulse of quantum light. In particular, we focus on the estimation of the interaction strength between the pulse and a two-level atom, equivalent to the estimation of the dipole moment. Our analysis of single-photon pulses highlights the interplay between the information gained from the absorption of the photon by the atom as measured in absorption spectroscopy, and the perturbation to the temporal mode of the photon due to spontaneous emission. Beyond the single-photon regime, we introduce an approximate model to study more general states of light in the limit of short pulses, where spontaneous emission can be neglected. We also show that for a vast class of entangled biphoton states, quantum entanglement between the signal mode interacting with the atom and the idler mode provides no fundamental advantage and the same precision can be obtained with a separable state. We conclude by studying the estimation of the electric dipole moment of a sodium atom using quantum light. Our work initiates a quantum information theoretic methodology for developing the theory and practice of quantum light spectroscopy.
