发表机构
Physikalisch-Technische Bundesanstalt; Leibniz Universität Hannover（德国联邦物理技术研究院; 汉诺威莱布尼茨大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
提出并数值验证了一种确定性协议，利用三维螺旋结构平面化在二维单物种离子库仑晶体中制备可控拓扑缺陷，实现单扭结和多扭结的可重复制备，并研究了缺陷相互作用与调控。
AI 中文摘要
我们提出并数值展示了一种确定性协议，用于在射频阱中约束的二维单物种库仑晶体中制备和定制拓扑缺陷。在传统的通过线性-锯齿形转变的有限速率淬火中，缺陷从独立选择的破缺对称域中随机形成，淬火速率控制着最终的畴结构。我们转而使用初始的三维螺旋结构，并将其平面化为确定性的缺陷态。我们证明，扭结的数量和近似轴向位置由初始螺旋的投影节点编码。我们发现，选定的螺旋在平面化过程中可以停留在亚稳的有限缠绕分支上，即使在绝热极限下也能产生可重复的单扭结或多扭结态。将淬火速率作为额外的控制参数，可以显著扩大能产生缺陷态的前驱螺旋集合，因为快速平面化可以防止淬火过程中的重排，并冻结预先存在的畴模式。平面化后，缺陷的存活和相互作用由其有效的Peierls-Nabarro势景观决定。通过数值分离两种缺陷类型的相互作用能，我们发现扩展扭结的相互作用在研究的参数范围内是吸引的，而奇数扭结则表现出短程排斥势垒，该势垒可通过陷阱势的各向异性α进行调节。最后，我们引入了一种基于实验动机的后选择方案，其中α被用于选择性地使目标缺陷失稳、湮灭或转化。我们的结果为在单物种库仑晶体中确定性制备单扭结和多扭结提供了途径，从而能够对缺陷相互作用、输运和纳米摩擦进行受控研究。
英文摘要
We propose and numerically demonstrate a deterministic protocol for preparing and tailoring topological defects in two-dimensional single-species Coulomb crystals confined in radio-frequency traps. In conventional finite-rate quenches through the linear-to-zigzag transition, defects form stochastically from independently chosen broken-symmetry domains, and the quench rate controls the resulting domain structure. We instead use an initial three-dimensional helix structure and planarize it into a deterministic defected state. We demonstrate that the number and approximate axial positions of kinks are encoded by the projected nodes of the initial helix. We find that selected helices can remain on metastable finite-winding branches during planarization and yield reproducible single- or multi-kink states, even in the adiabatic limit. Using the quench rate as an additional control parameter substantially enlarges the set of precursor helices that result in defected states, as a fast planarization can prevent reordering during the quench and freeze in the pre-existing domain pattern. After planarization, the survival and mutual interaction of the defects are governed by their effective Peierls--Nabarro potential landscape. By numerically isolating the interaction energy for the two defect types, we find that the interaction of extended kinks is attractive over the investigated parameter range, while odd kinks exhibit a short-range repulsive barrier tunable by the anisotropy of the trapping potential $α$. Finally, we introduce an experimentally motivated post-selection scheme in which $α$ is used to selectively destabilize, annihilate, or convert targeted defects. Our results provide a route to deterministic single- and multi-kink preparation in single-species Coulomb crystals, enabling controlled studies of defect interactions, transport, and nanofriction.
Comments23 pages, 15 figures
