Anisotropic interactions in an ultracold Dysprosium gas

超冷镝气体中的各向异性相互作用

• 批准号: 287321116
• 负责人: Professor Dr. Tilman Pfau
• 金额: --
• 依托单位: 5. Physikalisches Institut
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2016
• 资助国家: 德国
• 起止时间: 2015-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/287321116?language=en
• 关键词: Anisotropic; interactions; ultracold; Dysprosium; gas

Our ab-initio understanding of macroscopic quantum phenomena like superconductivity, superfluidity or quantum magnetism relies on microscopic theoretical models which involve interacting constituents like electrons, holes, atoms or quasiparticles. Strong interactions often result in strong quantum correlations which sometimes render theoretical models intractable, but e.g. allow for new states of matter in the presence of topological order and robust ground state degeneracy. Experimentally, the microscopic understanding at the level of individual particles is often inaccessible, and only averaged or macroscopic quantities/observables are probed. Quantum gas microscopes for two-dimensional arrangements of ultracold atoms have led to a new paradigm in the field as they allow to detect spatial configurations particle by particle and therefore grant access to the microscopic (quantum-) correlations. Here we propose to implement a spatial-, energy- and spin-resolved quantum gas microscope for the most magnetic atom, Dysprosium, which allows for both fermionic and bosonic ensembles with proven control over long and short range interactions. To maximize the effect of the nearest-neighbour interaction due to the dipole-dipole interaction we will use a near UV lattice at around 360 nm. With this the nearest-neighbour interactions will be enhanced by a factor of six compared to previous experiments. To be able to image single atoms on the UV lattice, the microscope will be based on an energy-dependent shelving technique using a long-lived electronic state as well as a state-of-the-art magnetic field control. Using the shelving technique the so called "super-resolution" limit of microscopy can be reached, which provides a significant improvement over the Abbe limit. This it is done for example in biology using stochastic optical reconstruction microscopy (STORM) or more recently in cold atoms using atomic localisation through a dark state. This atom-by-atom-approach will be used to unravel the microscopic nature of various macroscopic quantum phenomena: new phases of matter with strong nearest-neighbour interactions, e.g. Haldane chain or stripe phase in 2D, and quantum magnetism in lattice spin models. It is not clear whether short-range correlations exist in the recently discovered quantum droplets, but with our proposed experimental tool we will be able to freeze the droplets in the UV lattice and then measure the macroscopic correlations and therefore challenge the existing theory. The microscopic analysis will test theoretical models and bridge the gap between emergent macroscopic quantum phenomena and their underlying microscopic ingredients

我们对宏观量子现象（如超导性，超流体或量子磁性）的理解取决于微观理论模型，这些模型涉及电子，孔，原子或准原子等相互作用。强烈的相互作用通常会导致强大的量子相关性，有时会使理论模型难以理解，例如在存在拓扑顺序和强大的基态堕落的情况下，允许物质的新状态。在实验上，在单个颗粒水平上的微观理解通常是无法访问的，并且仅探测平均或宏观的数量/观察力。超电原子二维排列的量子气体显微镜已导致了现场的新范式，因为它们允许通过粒子检测空间构型粒子，因此授予了对显微镜（量子）相关性的访问。在这里，我们提议为最​​磁原子，dysprosium实施空间，能量和自旋分辨的量子显微镜，这允许在长距离和短范围相互作用中进行良好的控制。为了最大程度地提高由于偶极 - 偶极相互作用而导致的最近邻次相互作用的效果，我们将在360 nm左右使用接近的UV晶格。与以前的实验相比，最接近的邻居相互作用将增加6倍。为了能够在紫外线晶格上成像单个原子，显微镜将基于使用长寿命的电子状态以及最先进的磁场控制的能量依赖性搁架技术。使用搁架技术，可以达到所谓的“超分辨率”限制显微镜，这比ABBE极限可显着改善。这是在生物学上使用随机光学重建显微镜（Storm）或最近在冷原子中使用原子定位通过黑暗状态完成的。这种逐个原子的方法将用于揭示各种宏观量子现象的微观性质：物质的新阶段，具有强烈的最接近的纽布相互作用，例如2D中的Haldane链或条纹相，以及晶格自旋模型中的量子磁性。目前尚不清楚最近发现的量子液滴中是否存在短距离相关性，但是使用我们提出的实验工具，我们将能够冻结紫外线晶格中的液滴，然后测量宏观相关性，从而挑战现有理论。显微镜分析将测试理论模型并弥合出现的宏观量子现象及其潜在的显微成分之间的差距