Junctions are fundamental elements that support qubit locomotion in two-dimensional ion trap arrays and enhance connectivity in emerging trapped-ion quantum computers. In surface ion traps they have typically been implemented by shaping radio frequency (RF) electrodes in a single plane to minimize the disturbance to the pseudopotential. However, this method introduces issues related to RF lead routing that can increase power dissipation and the likelihood of voltage breakdown. Here, we propose and simulate a novel two-layer junction design incorporating two perpendicularly rotoreflected (rotated, then reflected) linear ion traps. The traps are vertically separated, and create a trapping potential between their respective planes. The orthogonal orientation of the RF electrodes of each trap relative to the other provides perpendicular axes of confinement that can be used to realize transport in two dimensions. While this design introduces manufacturing and operating challenges, as now two separate structures have to be precisely positioned relative to each other in the vertical direction and optical access from the top is obscured, it obviates the need to route RF leads below the top surface of the trap and eliminates the pseudopotential bumps that occur in typical junctions. In this paper the stability of idealized ion transfer in the new configuration is demonstrated, both by solving the Mathieu equation analytically to identify the stable regions and by numerically modeling ion dynamics. Our novel junction layout has the potential to enhance the flexibility of microfabricated ion trap control to enable large-scale trapped-ion quantum computing.

中文翻译：

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二维阵列的双层离子阱设计

结是支持二维离子阱阵列中的量子位运动并增强新兴捕获离子量子计算机中的连接性的基本元素。在表面离子阱中，它们通常通过在单个平面上塑造射频 (RF) 电极来实现，以最大限度地减少对赝电势的干扰。然而，这种方法引入了与射频引线布线相关的问题，这些问题会增加功耗和电压击穿的可能性。在这里，我们提出并模拟了一种新颖的两层结设计，其中包含两个垂直的旋转反射（旋转，然后反射）线性离子陷阱。这些陷阱是垂直分开的，并在它们各自的平面之间产生捕获电位。每个陷阱的射频电极相对于另一个的正交方向提供了垂直的限制轴，可用于实现二维传输。虽然这种设计带来了制造和操作方面的挑战，因为现在两个独立的结构必须在垂直方向上相对于彼此精确定位，并且来自顶部的光学接入被遮挡，但它消除了在顶部表面下方布线射频引线的需要。捕获并消除典型结点中出现的赝势凸块。本文通过解析求解 Mathieu 方程以确定稳定区域以及对离子动力学进行数值建模，证明了新构型中理想化离子转移的稳定性。我们新颖的结布局有潜力增强微制造离子阱控制的灵活性，以实现大规模捕获离子量子计算。