High-Resolution Quantum Gas Microscopy of Ultracold 23Na40K Molecules Trapped in Optical Lattices

量子计算机可能会解决任何经典计算机都无法想象的问题，这一承诺是物理学家几十年来推动当今技术边界进一步发展的主要动机，目的是同时和单独地利用一大群粒子的量子性质。在这些年里，在几个平台上取得了重大的概念和技术进步，包括光子、囚禁离子、超冷原子、超导量子比特，以及最近的马约拉纳费米子。然而，直到今天，还没有竞争者能够严格地证明量子设备相对于经典设备的真正加速。我们提出了一种新的基于光学晶格中捕获的超冷偶极23Na40K分子的多用途量子硬件。超冷分子代表了一个全新的平台，它借鉴了超冷原子的技术和可扩展性，并将其与偶极分子的可调远程相互作用相结合。为了在单分子水平上研究和控制相互作用，我们将建造一个分子量子气体显微镜，到目前为止，这仍然是一个突出的挑战。实现这种分子量子气体显微镜的难点之一是达到所需的偶极双碱分子的数目和简并度。这反过来又受到两个超冷原子转化为所谓的费什巴赫分子的效率的限制。我们提出了一种新的方法，通过受激速绝热通道(STIRAP)将玻色极化子转化为分子，从而产生处于振转基态的分子。这种方法有望显著提高转换效率，有可能直接产生超冷分子的简并气体。创造后，我们将把超冷的23Na40K分子加载到三维光学晶格的单层中。一个高分辨率的物镜将使我们能够以单格点分辨率成像分子，从而打开研究各种具有远程相互作用的多体效应的大门。我们还计划通过紧密聚焦的激光来局部控制单个分子的电偶极矩，从而证明两量子比特门的概念实现。获得对囚禁在光学晶格中的简并偶极23Na40K分子的量子本质的控制，是一种多用途量子硬件的缩影，非常适合于量子计算、量子模拟和精确测量。

The promise that quantum computers may solve problems unthinkable for any classical computer has been a leading motivation for physicists over decades to push today’s boundaries of technology further in an effort to harness simultaneously and individually the quantum properties of a large ensemble of particles. During these years, significant conceptual and technological advances have been achieved on several platforms including photons, trapped ions, ultracold atoms, superconducting qubits, and most recently Majorana fermions. However, until the present day no contender has been able to rigorously demonstrate a genuine speedup of quantum over classical devices. We here propose to build a novel multipurpose quantum hardware based on ultracold dipolar 23Na40K molecules trapped in an optical lattice. Ultracold molecules represent a radically new platform which borrows the techniques and scalability from ultracold atoms and combines it with the tunable long-range interactions of dipolar molecules. To study and control the interactions at the single molecule level we will build a molecular quantum gas microscope which remains – so far – an outstanding challenge. One of the difficulties in realizing such a molecular quantum gas microscope is to reach the required number and degeneracy of dipolar bi-alkali molecules. This in turn is limited by the efficiency at which two ultracold atoms can be converted into a so-called Feshbach molecule. We here propose a new pathway of creating molecules in their rovibrational ground state by converting Bose polarons into molecules through a stimulated rapid adiabatic passage (STIRAP). This approach holds promise to significantly enhance the conversion efficiency, potentially allowing the direct creation of a degenerate gas of ultracold molecules. After creation, we will load the ultracold 23Na40K molecules into a single layer of a three-dimensional optical lattice. A high-resolution objective will enable us to image the molecules with single lattice site resolution, thereby opening the doors to study a variety of many-body effects with long-range interaction. We further plan to demonstrate a proof of concept realization of a two-qubit gate by locally controlling the electric dipole moment of individual molecules through tightly focused laser beams. Gaining control over the quantum nature of degenerate dipolar 23Na40K molecules trapped in an optical lattice represents an epitome of a multipurpose quantum hardware ideally suited for quantum computations, quantum simulations, and precision measurements.