发表机构
Intelligent Data Analysis Laboratory (IDAL), Departament d’Enginyeria Electrònica, ETSE-UV, Universitat de València; Kipu Quantum（瓦伦西亚大学电子工程系智能数据分析实验室; 基普量子）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
提出一种数字化-模拟反绝热方法，利用绝热规范势结构制备表面码基态，通过固定角度XY门和模拟交换作用生成四体反绝热项，显著提升短时间基态制备质量，并将纠缠深度降低一个数量级。
AI 中文摘要
在超导电路中，使用浅层电路制备稳定子码态是近期量子纠错的重要基础操作，其中逻辑态初始化需要从本征的单体和两体控制中产生四体稳定子关联。我们提出了一种用于制备表面码基态流形的数字化-模拟方法。该方法利用绝热规范势的结构性质，通过固定角度的两量子比特XY门、单量子比特旋转和模拟交换相互作用演化，将稳定子局域反绝热项映射到超导布局上的数字化-模拟模块。这些修饰后的模块生成高阶算子，用作变分拟设，以在Sels-Polkovnikov绝热规范势框架内确定反绝热项。我们基准测试了棋盘格稳定子网格，最大可达4×4，其中方形网格实例对应旋转表面码，而矩形情况则检验方法的扩展性。对于所有网格，所提出的方法都能生成主要的四体反绝热基，并且在短演化时间内，与裸绝热演化相比，显著提高了基态制备质量。我们进一步将构造推广到n×m稳定子晶格，并表明数字化-模拟合成可以将纠缠深度降低一个数量级。综合来看，这些结果建立了稳定子几何结构、反绝热规范势结构与数字化-模拟控制之间的直接联系，用于在近期超导架构上无测量地制备稳定子码态。
英文摘要
Preparing stabilizer-code states with shallow circuits is an important primitive for near-term quantum error correction in superconducting circuits, where logical-state initialization requires four-body stabilizer correlations from native one- and two-body controls. We introduce a digital-analog method for the preparation of surface-code ground-state manifolds. The method exploits a structural property of the adiabatic gauge potential, mapping stabilizer-local counterdiabatic terms to digital-analog blocks on the superconducting layout using fixed-angle two-qubit XY gates, single-qubit rotations, and analog exchange-interaction evolutions. The dressed blocks generate higher-order operators used as the variational ansatz to determine the counterdiabatic terms within the Sels-Polkovnikov adiabatic-gauge-potential framework. We benchmark checkerboard plaquette-stabilizer grids up to 4 x 4; the square-grid instances correspond to rotated surface codes, while the rectangular cases probe the scaling of the method. For all grids, the proposed method generates the dominant four-body counterdiabatic basis and, at short evolution times, substantially improves ground-state preparation compared with bare adiabatic evolution. We further generalize the construction to n x m stabilizer lattices and show that digital-analog synthesis can reduce the entangling depth by an order of magnitude. Together, these results establish a direct connection between stabilizer geometry, the structure of the counterdiabatic gauge potential, and digital-analog control for measurement-free preparation of stabilizer-code states on near-term superconducting architectures.
