In this work, quantum metrology techniques are applied to the imaging of objects with a nonuniform refractive spatial profile. A sensible improvement on the classical accuracy is shown to be found when the “Twin Beam (TWB) State” is used. In particular, exploiting the multimode spatial correlation, naturally produced in the Parametric Down Conversion (PDC) process, allows a 2D reconstruction of complex spatial profiles, thus enabling an enhanced imaging. The idea is to use one of the spatially multimode beams to probe the sample and the other as a reference to reduce the noise. A similar model can also be used to describe wave front distortion measurements. The model is meant to be followed by a first experimental demonstration of such enhanced measurement scheme.

中文翻译：

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非均匀折射分布的量子增强成像

在这项工作中，量子计量技术被应用于具有不均匀折射空间分布的物体的成像。当使用“双光束 (TWB) 状态”时，可以发现经典精度的显着提高。特别是，利用在参数下转换 (PDC) 过程中自然产生的多模空间相关性，可以对复杂的空间轮廓进行 2D 重建，从而实现增强的成像。这个想法是使用空间多模光束中的一个来探测样品，另一个作为参考来降低噪声。类似的模型也可用于描述波前失真测量。该模型旨在对这种增强的测量方案进行第一次实验演示。