德国蒂宾根大学Wilson S. Martins团队研究了微运动和场轴失准对保罗阱中离子里德伯态激发的影响。该研究于2025年4月7日发表在《物理评论A》杂志上。

阱离子是量子模拟和计算最先进的平台之一。通过利用电子高度激发的里德伯态，可以进一步增强它们的能力，从而实现长距离电偶极相互作用。迄今为止，大多数实验和理论研究都集中在线性保罗阱中离子里德伯态的激发上，该阱通过静电场和振荡电场的组合产生约束。这两个场需要仔细对齐，以尽量减少由含时电场引起的所谓微动。这项工作的目的是系统地了解当两个电场的对称轴不一致时，微动对里德伯激发光谱的定性影响。

考虑到这种情况不仅在可能的场失准的情况下很重要，而且对于二维和三维离子晶体中的里德伯激发来说也是不可避免的，研究组开发了一个描述单个捕获里德伯离子的最小模型，他们通过Floquet理论对其进行了数值求解，并使用微扰方法进行了分析。研究组计算了激发光谱，并分析了可寻址和能量隔离的里德伯线在哪些参数范围内持续存在，这是进行相干操作的重要要求。

附：英文原文

Title: Impact of micromotion and field-axis misalignment on the excitation of Rydberg states of ions in a Paul trap

Author: Wilson S. Martins, Joseph W. P. Wilkinson, Markus Hennrich, Igor Lesanovsky

Issue&Volume: 2025/04/07

Abstract: Trapped ions are among the most advanced platforms for quantum simulation and computation. Their capabilities can be further augmented by making use of electronically highly excited Rydberg states, which enable the realization of long-range electric dipolar interactions. Most experimental and theoretical studies so far have focused on the excitation of ionic Rydberg states in linear Paul traps, which generate confinement by a combination of static and oscillating electric fields. These two fields need to be carefully aligned to minimize so-called micromotion, caused by the time-dependent electric field. The purpose of this work is to systematically understand the qualitative impact of micromotion on the Rydberg excitation spectrum, when the symmetry axes of the two electric fields do not coincide. Considering this scenario not only is important in the case of possible field misalignment but becomes inevitable for Rydberg excitations in two- and three-dimensional ion crystals, we develop a minimal model describing a single trapped Rydberg ion, which we solve numerically via Floquet theory and analytically using a perturbative approach. We calculate the excitation spectra and analyze in which parameter regimes addressable and energetically isolated Rydberg lines persist, which are important requirements for conducting coherent manipulations.

DOI: 10.1103/PhysRevA.111.043106

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.111.043106