Laser system for Quantum Gas Microscopy of dynamical gauge fields with Yb atoms

用于光学晶格中超冷原子的量子气体显微镜在模拟重要的凝聚态物质模型方面取得了显著的成功，特别是通过利用对模型参数的精确实验控制。结合规范场，更准确地说是动态规范场，可以将先前证明的实验概念推广到模拟晶格规范理论，这在描述量子电动力学或高能物理中的许多现象中起着重要作用。点阵规范理论需要实现局部对称性，这阻碍了这种理论在大系统中的成功实现。通过这个实验，我们计划开发一种新的晶格设置，提供隧道耦合的局部控制，这是实现U(1)晶格规范理论方案的基础，其中物质和规范场自由度可以用单个费米子种实现。完整的系统由四个主要部分组成：1)为了实现量子模拟的快速周期时间，我们计划使用行波几何实现快速和鲁棒的光传输。这一潜力将在1064nm的低噪声高频激光器中实现，该激光器也可用于光学偶极子阱。快速的周期时间对于高阶相关函数的测量是必不可少的，这需要极高的统计量。同时，较短的周期时间是有益的，当涉及到尽量减少实验中不必要的波动漂移，从而提供更可靠的数据采集。2)隧道耦合局部控制的实验技术基于一种特殊的状态相关晶格，该晶格还将用于单点分辨成像。3)为了获得晶格中冷费米子的内部态和密度分布的详细信息，我们计划在1064nm和532nm处安装一个垂直超晶格，允许使用拓扑自旋泵浦观察多体态的自旋和密度分布。4)为了控制用于状态相关电位的不同激光器的频率，需要具有良好绝对精度的波计。这使我们能够稳定激光频率，从而使状态相关的势长时间保持恒定。计划中的实验装置将首次在大型晶格系统中提供隧道耦合的局部控制。这是实现局部对称性和晶格规范理论的理想起点。该方案的成功实现为将多体系统的量子模拟扩展到其他研究领域，如高能物理，提供了一个独特的机会。

Quantum Gas Microscopes for ultracold atoms in optical lattices have been remarkably successful in simulating important condensed matter models, in particular, by making use of the precise experimental control of the model parameters. In combination with gauge fields, more precisely dynamical gauge fields, the previously demonstrated experimental concepts could be generalized to simulate lattice gauge theories, which play an important role in describing many phenomena in quantum electrodynamics or high-energy physics. Lattice gauge theories require the realization of local symmetries, which up to know hinder successful implementations of such theories in large systems. With this experiment we plan to develop a novel lattice setup that offers a local control of tunnel couplings, which are the basis for a scheme to realize U(1) lattice gauge theories, where matter and gauge-field degrees of freedom can be implemented with a single fermionic species.The complete system consists of four main parts: 1) In order to achieve fast cycle times for quantum simulation, we plan to implement a fast and robust optical transport using a running-wave geometry. The potential will be realized with low-noise high-frequency lasers at 1064nm, which can also be used for optical dipole traps. Fast cycle times are essential for measurements of higher-order correlation functions, which require extremely high statistics. At the same time, short cycle times are beneficial, when it comes to minimizing unwanted drifts of fluctuations in the experiment and therefore offer a more reliable data taking. 2) The experimental technique for the local control of tunnel couplings is based on a special state-dependent lattice, which in addition will be used for single-site resolved imaging. To reach the required lattice depths we will use a Ti:Sa Lasersystem at 760nm. 3) To obtain detailed information about the internal-state and density distribution of the cold fermions in the lattice we plan to install a vertical superlattice at 1064nm and 532nm, which allows for an observation of the spin- and density distribution of the many-body state using topological spin pumping. 4) In order to control the frequency of the different lasers used for the state-dependent potentials, a wave meter with good absolute accuracy is needed. This allows us to stabilize the laser frequency and therefore keep the state-dependent potential constant for long times.The planned experimental setup will offer for the first time a local control of tunnel couplings in a large lattice systems. This is an ideal starting point for the implementation of local symmetries and hence lattice gauge theories. A successful realization of this scheme constitutes a unique opportunity to extend quantum simulations of many-body systems to other research areas, such as high-energy physics.