Moskal Paweł, Kumar Deepak, Sharma Sushil, Beyene Ermias Yitayew, Chug Neha, Coussat Aurélien, Curceanu Catalina, Czerwiński Eryk, Das Manish, Dulski Kamil, Gorgol Marek, Jasińska Bożena, Kacprzak Krzysztof, Kaplanoglu Tevfik, Kapłon Łukasz, Kozik Tomasz, Lisowski Edward, Lisowski Filip, Mryka Wiktor, Niedźwiecki Szymon, Parzych Szymon, Del Rio Elena P, Rädler Martin, Skurzok Magdalena, Stepień Ewa Ł, Tanty Pooja, Ardebili Keyvan Tayefi, Eliyan Kavya Valsan
Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, S. Łojasiewicza 11, 30-348 Kraków, Poland.
Total-Body Jagiellonian-PET Laboratory, Jagiellonian University, 30-348 Kraków, Poland.
Sci Adv. 2025 May 2;11(18):eads3046. doi: 10.1126/sciadv.ads3046. Epub 2025 Apr 30.
In state-of-the-art positron emission tomography (PET), information about annihilation photon polarization is unavailable. Here, we present a PET scanner built from plastic scintillators, where annihilation photons primarily interact via the Compton effect, providing information about both photon polarization and propagation direction. Using this plastic-based PET, we determined the distribution of the relative angle between polarization planes of photons from positron-electron annihilation in a porous polymer. The amplitude of the observed distribution is smaller than predicted for maximally quantum entangled two-photon states but larger than expected for separable photons. This result can be well explained by assuming that photons from pick-off annihilation are not entangled, while photons from direct and parapositronium annihilations are maximally entangled. Our result indicates that the degree of entanglement depends on the annihilation mechanism in matter, opening avenues for exploring polarization correlations in PET as a diagnostic indicator.
在最先进的正电子发射断层扫描（PET）中，关于湮灭光子极化的信息是无法获取的。在此，我们展示了一种由塑料闪烁体构建的PET扫描仪，其中湮灭光子主要通过康普顿效应相互作用，从而提供有关光子极化和传播方向的信息。使用这种基于塑料的PET，我们确定了多孔聚合物中正电子 - 电子湮灭产生的光子极化平面之间相对角度的分布。观察到的分布幅度小于最大量子纠缠双光子态的预测值，但大于可分离光子的预期值。通过假设来自挑选湮灭的光子不纠缠，而来自直接和仲正电子湮灭的光子最大程度地纠缠，可以很好地解释这一结果。我们的结果表明，纠缠程度取决于物质中的湮灭机制，为探索PET中的极化相关性作为诊断指标开辟了途径。
