Optical low-coherence reflectometry is capable of unambiguously measuring positions of stacked, partially reflective layers in a sample object. It relies on the low coherence of the light source and the absolute distances are obtained from the position reading of a mechanical motor stage. We show how to exploit the simultaneous high and low coherence properties of energy-time entangled photon pairs to directly calibrate the position scale of an optical low coherence reflectometry scan with a reference laser wavelength. In the experiment, a precision of 1.6 nm and good linearity is demonstrated.

中文翻译：

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具有能量时间纠缠光子的自校准光学低相干反射法，用于绝对距离测量

光学低相干反射法能够明确地测量样品物体中堆叠的部分反射层的位置。它依赖于光源的低相干性，并且绝对距离是从机械马达平台的位置读数获得的。我们展示了如何利用能量时间纠缠光子对的同时高和低相干特性来直接校准参考激光波长的低相干反射光学扫描的位置尺度。在实验中，证明了1.6 nm的精度和良好的线性度。