论文标题
设计基于卓越点的图表，可提供拓扑保证的量子搜索
Designing exceptional-point-based graphs yielding topologically guaranteed quantum search
论文作者
论文摘要
量子步行是重要的量子计算算法类别的基础，并代表各种模拟和实际应用中的有前途的方法。在这里，我们设计了经频镜监测的量子步道及其后续图，可以自然增加目标搜索。我们展示了如何与该特性构造行走，这些特性的所有特征值是非富帝生存操作员的所有特征值，描述了单一动力学的混合效应和测量的背部效果，凝聚为零，对应于一个特殊点，其程度是该系统的大小。通常，在任何初始条件下，可以保证在有限的时间内取得成功的搜索，该条件比典型图表上的经典随机步行或量子步行更快。然后，我们展示了这种有效的量子搜索如何与量化的拓扑缠绕数有关，并进一步讨论问题与有效的无质量狄拉克粒子的联系。
Quantum walks underlie an important class of quantum computing algorithms, and represent promising approaches in various simulations and practical applications. Here we design stroboscopically monitored quantum walks and their subsequent graphs that can naturally boost target searches. We show how to construct walks with the property that all the eigenvalues of the non-Hermitian survival operator, describing the mixed effects of unitary dynamics and the back-action of measurement, coalesce to zero, corresponding to an exceptional point whose degree is the size of the system. Generally, the resulting search is guaranteed to succeed in a bounded time for any initial condition, which is faster than classical random walks or quantum walks on typical graphs. We then show how this efficient quantum search is related to a quantized topological winding number and further discuss the connection of the problem to an effective massless Dirac particle.
