基于冷原子干涉的标量阿哈罗诺夫-玻姆效应拓扑特性研究

The Aharonov-Bohm effect (AB effect) is an important interference effect in quantum mechanics, which indicates that nonzero potentials could still affect the phase of wave function of a microscopic particle even though there are no forces in the moving path of the particle, and this influence could be shown by means of matter wave interferometry. In recent years, the AB effect induced by scalar potential has been investigated widely, however, the essence of topological characteristics of this effect is still unclear up to now. This subject is going to study the scalar AB effect and its topological characteristics by using cold atom interferometer consisted of four Raman pulses, and the scalar potential is produced by the quadratic Zeeman effect of the atom. The aim of this subject is to enhance the understanding of the nature of quantum mechanics topological phase. The main contents include: 1)The geometric topological property of the scalar AB effect will be investigated by the exploration of the dependence of the phase of interference fringe on the moving paths and the enclosed area of the interference paths; 2)The nondispersive feature of scalar AB effect could be studied by analyzing the changes of contrast of the atomic interference fringe with the scalar potentials and the velocity of cold atoms; 3)The experimental verification of the scalar AB effect could be carried on precisely by measuring the quantitative relationship between the phase shifts of the interference fringes and the amplitude of the scalar potential. The investigation of topological features of scalar AB effect in this subject is beneficial for the further comprehension of the basic theory of quantum mechanics, and valuable for the potential applications in the improvement of performance of quantum sensors such as atomic clock, atomic gravimeter, etc.

阿哈罗诺夫-玻姆效应(AB效应)是量子力学中一种重要的干涉效应，它指出微观粒子即使未受到力的作用，其波函数的相位仍会受到势的影响，且这种影响可通过物质波干涉体现出来。近些年，由标量势诱导的AB效应已经被广泛研究，但其拓扑特性的本质至今仍不清楚。本课题利用原子的二阶塞曼效应产生标量势，并基于四脉冲冷原子干涉仪，研究标量势诱导的标量AB效应及其拓扑特性，以期增进对量子力学拓扑相位本质的认识。课题主要研究内容包括：1)通过探究干涉条纹相位与原子运动路径、干涉面积之间的关系，研究标量AB效应的几何拓扑性质；2)通过分析干涉条纹对比度随标量势、原子速度的变化，研究标量AB效应的非色散性质；3)通过测量干涉条纹相移与标量势的定量关系，在实验上精确验证标量AB效应。本课题对标量AB效应拓扑特性的研究有利于加深对量子力学基础理论的理解，并在提升原子钟、原子重力仪等量子传感器性能方面有潜在的应用价值。

阿哈罗诺夫-玻姆效应(AB效应)是量子力学中一种重要的干涉效应，它指出微观粒子即使未受到力的作用，其波函数的相位仍会受到势的影响，且这种影响可通过物质波干涉体现出来。虽然由标量势诱导的AB效应已经被广泛研究，但其拓扑特性的本质至今仍不清楚。.本项目的主要研究内容是利用原子的二阶塞曼效应产生标量势，并基于双脉冲冷原子干涉仪，研究标量势诱导的标量AB效应及其拓扑特性。在实验研究中，课题组实现了冷原子团制备、冷原子量子态纯化、拉曼脉冲序列与原子相互作用、原子荧光探测等过程，得到了原子干涉条纹。此外，通过在两个拉曼光脉冲之间作用偏置磁场脉冲，我们产生了一个有势却没有力的区域；随后，我们通过分析原子干涉条纹相位与所加磁场幅度，从实验上验证了标量AB效应。在标量AB效应的拓扑特性研究方面，课题组在实验上证实了标量AB效应的非色散性质，即原子干涉条纹的对比度不随外加标量势发生变化。这些实验结果有助于人们理解量子力学中势的重要作用，并为量子精密测量技术的发展提供了新思路。