First demonstration of interaction-free measurement protocol with x-rays

We propose a proof-of-concept experiment to demonstrate one of the most exotic and counter-intuitive quantum effects that enables the interrogation of samples with a significantly reduced dose compared to conventional probes. The effect that is known as interaction free measurements (IFM) relies on interference of single photons and on the fact that the energy quanta of a single photon cannot split. While the effect has been demonstrated by several groups with visible photons, ultra-cold atoms, and electrons it has never been demonstrated with x-rays. The demonstration of IFM with x-rays will open intriguing possibilities for measurements with reduced dose mainly for biological samples where radiation damage can be a significant limitation. On the fundamental side, the use of the high efficiency photon number resolving x-ray detectors can be used for the test of the effect at the theoretical limit, which is hard to do with optical photons.

本研究提出一项概念验证实验，用以展示一种极具奇异色彩且违背直觉的量子效应：该效应可在样品检测过程中，相较传统探测手段大幅降低辐射剂量。这一效应被称为无相互作用测量（Interaction Free Measurements, IFM），其核心依托单光子干涉现象，以及单光子的能量量子无法分割这一基本物理事实。尽管已有多个研究团队分别利用可见光光子、超冷原子与电子实现了该效应的验证，但此前从未有研究采用X射线完成相关演示。利用X射线实现无相互作用测量的演示，将为低剂量检测开辟极具吸引力的应用前景，尤其适用于辐射损伤会成为显著限制因素的生物样品检测场景。从基础研究层面而言，借助高效光子数分辨X射线探测器，可在理论极限条件下对该效应开展检验——这一工作在可见光光子的探测场景中难以实现。