{"title":"Computerized simulation of 2-dimensional phase contrast images using spiral phase plates in neutron interferometry","authors":"Wolfgang Treimer, Frank Haußer, Martin Suda","doi":"10.1515/zna-2024-0142","DOIUrl":null,"url":null,"abstract":"We present calculations of interferograms (interference patterns) of one or multiple spiral phase plates that would be observed with a perfect crystal neutron interferometer of Mach–Zehnder type. A spiral phase plate (SPP) in one of the two coherent beam paths produces a twist in the phase front and thus a vortex beam with intrinsic angular momentum, which in the case of neutrons should be observed as a characteristic interference pattern that appears complementary to each other in both detectors behind the interferometer. Adding additional SPPs in one beam path of the interferometer yield interference patterns similar to that of a single SPP but only due to the cumulative step height. All simulated interferograms have been calculated on the basis of dynamical neutron diffraction without any assumption of a neutron orbital angular momentum and show very convincing agreement with experimental results from the literature, see e.g. (C. W. Clark, R. Barankov, M. G. Huber, M. Arif, D. G. Cory, and D. A. Pushin, “Controlling neutron orbital angular momentum,” <jats:italic>Nature</jats:italic>, vol. 525, pp. 504–506, 2015). In particular, this clarifies, that the cited experiments do not give evidence of the quantization of interactions caused by a twist of the phase front of a neutron wave in the interferometer and thus no evidence for the effect of a neutron orbital angular momentum.","PeriodicalId":23871,"journal":{"name":"Zeitschrift für Naturforschung A","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Zeitschrift für Naturforschung A","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1515/zna-2024-0142","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
We present calculations of interferograms (interference patterns) of one or multiple spiral phase plates that would be observed with a perfect crystal neutron interferometer of Mach–Zehnder type. A spiral phase plate (SPP) in one of the two coherent beam paths produces a twist in the phase front and thus a vortex beam with intrinsic angular momentum, which in the case of neutrons should be observed as a characteristic interference pattern that appears complementary to each other in both detectors behind the interferometer. Adding additional SPPs in one beam path of the interferometer yield interference patterns similar to that of a single SPP but only due to the cumulative step height. All simulated interferograms have been calculated on the basis of dynamical neutron diffraction without any assumption of a neutron orbital angular momentum and show very convincing agreement with experimental results from the literature, see e.g. (C. W. Clark, R. Barankov, M. G. Huber, M. Arif, D. G. Cory, and D. A. Pushin, “Controlling neutron orbital angular momentum,” Nature, vol. 525, pp. 504–506, 2015). In particular, this clarifies, that the cited experiments do not give evidence of the quantization of interactions caused by a twist of the phase front of a neutron wave in the interferometer and thus no evidence for the effect of a neutron orbital angular momentum.
我们介绍了对一个或多个螺旋相板干涉图(干涉图案)的计算,这些干涉图可以通过马赫-泽恩德(Mach-Zehnder)型完美晶体中子干涉仪观测到。两个相干光束路径中的一个螺旋相位板(SPP)会在相位前沿产生扭曲,从而产生具有固有角动量的涡旋光束。在干涉仪的一条光束路径上添加额外的 SPP 会产生与单个 SPP 相似的干涉图,但这只是由于累积的阶跃高度所致。所有模拟干涉图都是在动态中子衍射的基础上计算得出的,没有任何中子轨道角动量的假设,并且与文献中的实验结果显示出非常令人信服的一致性,例如参见(C. W. Clark、R. Barankov、M. G. Huber、M. Arif、D. G. Cory 和 D. A. Pushin,"控制中子轨道角动量",《自然》,第 525 卷,第 504-506 页,2015 年)。这尤其说明,所引用的实验并不能证明干涉仪中的中子波相位前沿扭曲所导致的相互作用量子化,因此也就不能证明中子轨道角动量的影响。